| |
Chemistry Topics - 6.022e23mol-1
- Avogadro′s number
- 8.314 JK-1mol-1
- Molar gas constant.
- Abegg′s Rule
- This states that the difference between the maximum positive and negative valence of an element is frequently eight.
- Abel Flashpoint Apparatus
- A petroleum-testing apparatus for determining the flash point.
- Abietic Acid
C20H30O2 A resin acid that is the primary irritant in pine wood and pine resin. It is a glassy or partly crystalline yellowish solid. It belongs to the diterpene group of organic compounds. It is used in lacquers, varnishes, and soaps, and for the analysis of resins and the preparation of metal resinates. - Abietinic Acid
- Another name for Abietic Acid.
- Abram′s Law
- A rule that the ratio of water to cement for chemical action to impart strength to concrete is 0.85:1.
- Absolute Vacuum
- A volume which contains no matter.
- Absorbed Dose
- The amount of a chemical that enters the body of an exposed organism.
- Absorption Band
- A dark band in the absorption spectrum of a substance, corresponding to a range of wavelengths for which the substance absorbs more strongly than at adjacent wavelengths.
- Absorption Spectroscopy
- A technique for determining the concentration and structure of a substance by measuring the amount of electromagnetic radiation the sample absorbs at various wavelengths.
- Absorption Spectrum
- The collection of wavelengths missing from a continuous distribution of wavelengths.
- Abundance Ratio
- The ratio of the number of atoms of an isotope to the number of atoms of another isotope of the same element in a sample.
- Ac
- Actinium is a radioactive element.
- Accelerator
- A machine used to accelerate particles to high speeds.
- Acceptor
- An atom which is likely to take on one or more electrons when placed in a crystal.
- Acenaphthene
- Found in petroleum residues.
- Acenaphthoquinone
C12H6O2 A polycyclic aromatic hydrocarbon derived from naphthalene that is insoluble in water, but soluble in alcohol. It is used as an intermediate for the manufacturing of dyes, pharmaceuticals and pesticides. - Acenaphthylene
- A polycyclic aromatic hydrocarbon.
- Acepromazine
C19H22N2OS More commonly known as ACP it is a phenothiazine derivative antipsychotic drug. - Acetaldehyde
- Formed by the oxidation of ethanol this is a colourless fruity smelling liquid that with further oxidation forms acetic acid.
- Acetamide
- Colourless crystalline used industrially as a solvent.
- Acetaminophen
C8H9NO2 More commonly known as Paracetamol, a widely used over-the-counter analgesic. - Acetanilide
- Also known as Antifebrin this is a white crystalline solid.
- Acetic acid
- The acid contained in vinegar.
- Acetic Anhydride
- The anhydride of acetic acid, used in the manufacture of plastics.
- Acetoguanamine
C4H7N5 Used as a raw material for guanamine resins. It is used as a modifier and flexibilizer of formaldehyde resins and as a intermediate for pharmaceuticals. - Acetone
- Also known as Dimethyl Ketone, often used as a solvent.
- Acetonitrile
- Also known as Methyl Cyanide, a colourless poisonous liquid, used as a solvent and in organic synthesis.
- Acetophenone
- Colourless sweet smelling liquid, also known as Acetylbenzene and Phenyl Methyl Ketone.
- Acetyl Chloride
- Also known as Ethanoyl Chloride it is a colourless pungent liquid.
- Acetylbenzene
- Alternative name for Acetophenone.
- Acetylene
- Also known as Ethyne it is made by the action of water on calcium carbide.
- Acetyl-Salicyclic Acid
CH3COOC6H4COOH Commonly known as Aspirin, a white solid. Used in medicine as an antipyretic and analgesic. - Acheson Process
- The Acheson process is an industrial process for the manufacture of graphite by heating coke mixed with clay.
- Aciclovir
C8H11N5O3 One of the most commonly-used antiviral drugs, it is primarily used for the treatment of herpes simplex virus infections. - Acid
- Compound that gives off H+ ions in solution.
- Acid Air
- Alternative name for Hydrogen Chloride.
- Acid Anhydride
- Nonmetallic oxides or organic compounds that react with water to form acids.
- Acid Error
- A systematic error that occurs when glass pH electrodes are used in strongly acidic solutions.
- Acid Halide
- Compounds containing a carbonyl group bound to a halogen atom.
- Acid Rain
- Rain that is weakly acidic due to pollution.
- Acid-Base Indicator
- A weak acid that has acid and base forms with sharply different colours.
- Acidic
- Describes a solution with a high concentration of H+ ions.
- Acidic Solution
- A solution in which the hydrogen ion activity is higher than that of the hydroxide ion, when the solvent is water.
- Acidulant
- A substance added to food or beverages to lower pH and to impart a tart, acid taste.
- Acoustic Agglomeration
- High intensity sound waves are used in a fluid to group suspended particles into larger aggregates.
- Acraldehyde
- Alternative name for Acrolein.
- Acridine
C13H9N A colourless solid, was first isolated from coal tar. It is a raw material used for the production of dyes and some valuable drugs. - Acroleic Acid
- Alternative name for Acrylic Acid.
- Acrolein
C3H4O the simplest unsaturated aldehyde. It has a piercing, disagreeable, acrid smell similar to that of burning fat. - Acrylamide
C3H5NO A white odourless crystalline solid, soluble in water, ethanol, ether and chloroform. - Acrylic
- Synthetic resin made from acrylic acid or a derivative thereof; acrylics possess the property of transparency and offer flame resistance.
- Acrylic Acid
C3H4O2 The simplest unsaturated carboxylic acid with a vinyl group at the a-carbon position and a carboxylic acid terminus. - Acrylic Aldehyde
- Alternative name for Acrolein.
- Acrylonitrile
C3H3N Pungent-smelling colourless liquid that often appears yellow due to impurities. It is an important monomer for the manufacture of useful plastics. - Acryloyl Chloride
C3H3ClO A clear, light yellow, flammable liquid with an acrid smell. - Actinic
- Pertaining to electromagnetic radiation capable of initiating photochemical reactions.
- Actinide
- Elements 89-102 are called actinides.
- Actinium
- A radioactive element.
- Activated Charcoal
- A porous form of carbon that acts as a powerful adsorbent.
- Activated Complex
- State of highest energy during a reaction.
- Activation Energy
- For the forward reaction is the energy required to go from reactants to the transition state.
- Active Metal
- A metal that is easily oxidized in air.
- Active Site
- A pocket or crevice on an enzyme molecule that fits reactant molecules like a hand in a glove.
- Adakane 12
- Another name for Dodecane.
- Adamantane
C10H16 A colourless, crystalline compound with a camphor-like odour. It is a cycloalkane and also the simplest diamondoid. - Addition Reaction
- A chemical reaction in which two atoms or groups of atoms are added across a double bond.
- Additive
- A material added to another, usually in small amounts, to impart or enhance desirable properties or to suppress undesirable properties.
- Adhesive Tape
- A tape with a sticky substance on one side.
- Adipic Acid
- White crystalline solid used in the manufacture of nylon.
- Adipoyl Chloride
C6H8Cl2O2 A hazardous chemical that evolves HCl when reacted with water. Can be reacted with hexamethylene diamine to form nylon. - Adipoyl Dichloride
- Alternative name for Adipoyl Chloride.
- Adsorb
- To collect molecules of a substance on a surface.
- Adsorbent
- A substance that collects molecules of another substance on its surface.
- Adsorbtion Chromatography
- A technique for separating or analyzing mixtures that contain at least one component that is preferentially adsorbed by the stationary phase as it moves over it.
- Adsorbtion Indicator
- A substance that indicates an excess of a reactant in a precipitation reaction.
- Adulterants
- Chemical impurities or substances that by law do not belong in a food, or pesticide.
- Aeolotropy
- Aeolotropy is the antithesis of isotropy.
- Aeration
- Preparation of a saturated solution of air gases by either spraying the solution in air or by bubbling air through it.
- Aeration Tank
- A chamber used to inject air into water.
- Aerial Acid
- An old name for carbon dioxide.
- Aero Metal
- A metal used in casting made from aluminium, zinc and copper.
- Aerobic
- Requiring or occurring in the presence of oxygen.
- Aerosol
- A colloid in which solid particles or liquid droplets are suspended in a gas.
- Affinity
- Chemical attraction.
- Ag
- Silver is a pure white metallic element. The best electrical conductor and used in photographic emulsions.
- Ag2S
- Chemical formula for Silver Sulphide.
- Agar
- A gel made from seaweed used to make salt bridges.
- AgI
- Chemical formula for Silver Iodide.
- AgNO3
- Silver Nitrate.
- Air
- The main constituents of air are Nitrogen, Oxygen, Argon, Carbon Dioxide, Neon, Helium along with a number of other trace gases.
- Air Set Cement
- A cement that sets through loss of water.
- Al
- Aluminium is the basis for a number of alloys.
- Al2Br6
- Chemical formula for Aluminium Bromide.
- Al2I6
- Chemical formula for Aluminium Iodide.
- Al2O3
- Chemical formula for aluminium oxide.
- Al2O32H2O
- Chemical formula for Bauxite.
- Al2S3
- Chemical formula for Aluminium Sulphide.
- Alabamine
- The name originally proposed for Astatine.
- Alanine
C3H7NO2 An a-amino acid. It plays a key role in glucose-alanine cycle between tissues and liver. - Alcian Blue
C56H68Cl4CuN16S4 A phthalocyanine dye that contains copper. - AlCl3
- Chemical formula for Aluminium Chloride.
- Alcohol
- An alcohol is an organic compound with a carbon bound to a hydroxyl group.
- Aldehyde
- Prepared by the oxidation of primary alcohols so that the OH group loses its hydrogen to give an oxygen joined by a double bond to a carbon atom.
- Aldosterone
C21H28O5 A hormone that causes the tubules of the kidneys to retain sodium and water. - AlF3
- Chemical formula for Aluminium Fluoride.
- AlH3
- Chemical formula for Aluminium Hydride.
- Aliphatic
- An organic compound that does not contain ring structures.
- Aliquot
- A sample of precisely determined amount taken from a material.
- Alkali
- A substance that dissolves in water to give a solution of aqueous hydroxide ions that is capable of turning red litmus blue.
- Alkali Metal
- A metal in group IA of the periodic table that form strongly alkaline hydroxides.
- Alkaline
- Having a pH greater than 7.
- Alkaline Air
- An old name for ammonia gas.
- Alkaline Battery
- A storage battery which uses an alkaline electrolyte.
- Alkaline Earth
- An oxide of an alkaline earth metal, which produces an alkaline solution in reaction with water.
- Alkaline Earth Metal
- A metal in group IIA of the periodic table.
- Alkaline Error
- A systematic error that occurs when glass electrodes are used to read the pH of an extremely alkaline solution.
- Alkalinity
- A measure of a material's ability to neutralize acids.
- Alkaloid
- A class of bitter-tasting, basic organic compounds with nitrogen-containing rings.
- Alkane
- A series of organic compounds with general formula CnH2n+2.
- Alkene
- A compound that consists of only carbon and hydrogen, that contains at least one carbon-carbon double bond.
- Alkoxide
- An ionic compound formed by removal of hydrogen ions from the hydroxyl group in an alcohol using reactive metals.
- Alkyl
- A molecular fragment derived from an alkane by dropping a hydrogen atom from the formula -CnH2n+1.
- Alkyl Halide
- An alkyl group attached to a halogen atom.
- Alkyne
- A compound that consists of only carbon and hydrogen, that contains at least one carbon-carbon triple bond.
- Allo-
- A prefix that designates the more stable of a pair of geometric isomers.
- Allobar
- A form of an element that has isotopic abundances that are different from the naturally occuring form.
- Allomer
- Substances with different chemical composition but the same crystalline form.
- Allosteric Effect
- A change in the behaviour of one part of a molecule caused by a change in another part of the molecule.
- Allotriomorphic Crystal
- A crystal having a normal lattice structure, but with an imperfect outward shape due to the influence of its surroundings.
- Allotropy
- The reversible phenomenon by which certain metals may exist in more than one crystal structure.
- Alloy
- A metal produced by mixing other metals.
- Allyl
- A molecular fragment derived by removing a methyl hydrogen from propene.
- Allyl Alcohol
- Used in the manufacture of resins and many pharmaceuticals this is a colourless pungent liquid.
- Allyl Aldehyde
- Alternative name for Acrolein.
- Almond Artificial Essential Oil
- Alternative name for Benzaldehyde.
- AlN
- Chemical formula for Aluminium Nitride.
- Alpha Radiation
- A stream of alpha particles. Alpha rays rapidly dissipate their energy as they pass through materials, and are far less penetrating than beta particles and gamma rays.
- Alternating Copolymer
- A polymer, composed of two different repeating mers, in which the different mer units systematically alternate positions along the molecular chain.
- Alumel
- Trade name for an alloy of nickel with up to 5% aluminium, manganese and silicon, used with chromel in K-type thermocouples.
- Aluminium
- Basis for a number of alloys.
- Aluminium Bromide
Al2Br6 White or very pale yellow crystalline solid. - Aluminium Bronze
- A copper-aluminum alloy with high tensile strength and resistance to corrosion.
- Aluminium Chloride
- A chloride used as a wood preservative or catalyst.
- Aluminium Fluoride
AlF3 White crystalline solid. - Aluminium Hexabromide
- Alternative name for Aluminium Bromide.
- Aluminium Hexachloride
- Alternative name for Aluminium Chloride.
- Aluminium Hexaiodide
- Alternative name for Aluminium Iodide.
- Aluminium Hydride
AlH3 White crystalline solid. - Aluminium Hydroxide
- White crystalline compound that occurs naturally as the mineral gibbsite.
- Aluminium Iodide
Al2I6 White solid. - Aluminium Nitride
AlN Bluish white crystalline solid. - Aluminium Oxide
Al2O3 Alminium oxide is the most widely used oxide ceramic, either in pure form or as raw material to be mixed with other oxides. - Aluminium Sulphide
Al2S3 Yellow or yellow grey powder. - Aluminium Tribromide
- Alternative name for Aluminium Bromide.
- Aluminium Trichloride
- Alternative name for Aluminium Chloride.
- Aluminium Triiodide
- Alternative name for Aluminium Iodide.
- Am
- A radioactive element.
- Amagat
- The unit of density of a gas at stp equal to 44.614774 molm-3.
- Amalgam
- An alloy that contains mercury.
- Americium
- A radioactive element. Alpha particle emitter with a half life of 475 years.
- Amide
- The most stable of all the carbonyl functional groups.
- Amine
- A class of organic compounds in which one or more of the hydrogen atoms of ammonia have been replaced by other groups of atom.
- Aminic Acid
- Another name for Methanoic Acid.
- Amino Acid
- Amino acids are molecules that contain at least one amine group (-NH2) and at least one carboxylic acid group (-COOH).
- Aminoacetic Acid
- A naturally occurring aliphatic amino acid, also known as glycine.
- Aminobenzene
- Alternative name for Aniline.
- Ammine
- A metal ion complex containing ammonia as a ligand.
- Ammonia
- Obtained from nitrogen using the Haber process and used in the manufacture of fertilizers and explosives.
- Ammonium Carbonate
(NH4)2CO3 - Ammonium Chloride
NH4Cl A clear white water-soluble crystalline salt with a biting, slightly sour taste. - Ammonium Fluoride
NH4F Crystallizes as small prisms, having a sharp saline taste, and is exceedingly soluble in water. - Ammonium Hydrogenphosphate
(NH4)2HPO4 Used as a nutrient for the yeast in brewing. - Ammonium Hydroxide
- A solution of ammonia in water.
- Ammonium Iodide
NH4I Used in photographic chemicals and some medications. - Ammonium Ion
- NH4+ is a cation formed by neutralization of ammonia, which acts as a weak base.
- Ammonium Nitrate
NH4NO The most known chemical property of ammonium nitrate is its combustability. This also makes it a very dangerous compound to work with. - Ammonium Sulphate
(NH4)2SO4 Fine granulated, off white or brown crystals. There may be a slight ammonia like odour. Sulphate of ammonia is a chemical fertilizer. - Amorphography
- The branch of science concerned with the determination of amorphous solid structures and their systemmatic classification.
- Amorphous
- Non-crystalline, without long-range order.
- Amount of Substance
- The SI unit of the Amount of Substance is the mole.
- Amperometry
- Determining the concentration of a material in a sample by measuring electric current.
- Amphi-
- A prefix used to name certain members of a series of geometric isomers or stereoisomers.
- Amphiprotic Solvent
- Solvents that exhibit both acidic and basic properties.
- Amphoteric
- A substance that can act as either an acid or a base in a reaction.
- AMU
- Defined as one twelfth of the mass of the most abundant isotope of carbon (12C)
- Amyl Nitrite
C5H11NO2 Employed medically to treat heart diseases such as angina and also to treat cyanide poisoning. It is also used as an inhalant drug that induces a brief euphoria. - Amylopectin
- A form of starch made of glucose molecules linked in a branching pattern.
- Amylose
- A form of starch made of long, unbranched chains of -D-glucose molecules.
- Anaerobic
- Occurring in the absence of air or oxygen.
- Analyte
- The sample constituent whose concentration is sought in a chemical analysis.
- Angelic Acid
C5H8O2 A monocarboxylic unsaturated organic acid found in Angelica Archangelica as well as other plants. - Angstrom
- It is an old unit used for measuring the wavelength of electromagnetic radiation including visible light and X-rays.
- Anhydrous
- A compound with all water removed, especially water of hydration.
- Aniline
- Also known as Phenylamine or aminobenzene.
- Anion
- Ions with a negative charge.
- Anisole
- Also known as Methyl Phenyl Ether, an aromatic smell and used in perfumes.
- Anode
- The electrode where electrons are lost (oxidized) in redox reactions.
- Anodic Protection
- A technique to reduce the corrosion rate of a metal by polarizing it into its passive region, where dissolution rates are low.
- Anodic Reaction
- Electrode reaction equivalent to a transfer of positive charge from the electronic to the ionic conductor; an anodic reaction is an oxidation process.
- Anodize
- To coat a metal with a protective film by electrolysis.
- Anthocyanin
- A family of pigments that give flowers, fruits, and leaves of some plants their red or blue colouring.
- Anthracene
- White crystalline with a blue fluorescence used in the manufacture of dyes.
- Anthracite
- Type of coal with highest carbon content (86% to 98%) and thus highest heat value .
- Anthraquinone
- Yellow powder derived from Anthracene and used as a dye.
- Antichlor
- A chemical compound that reacts with chlorine-based bleaches to stop the bleaching.
- Antifebrin
- Alternative name for Acetanilide.
- Antimony
- Elemental antimony is generally found in one of two allotropes and has both metallic and non-metallic properties.
- Antimony Hydride
SbH3 Poisonous gas. Also known as Stibine. - Antioxidant
- Compounds that slow oxidation processes that degrade foods, fuels, rubber, plastic, and other materials.
- Antipyretic
- A substance that can lessen or prevent fever.
- Aprotic Solvent
- A solvent that does not act as an acid or as a base.
- Aqua Fortis
- Ancient name for Nitric Acid, a colourless, corrosive, acid liquid that attacks most metals and other substances.
- Aqua Regia
- A mixture of nitric and hydrochloric acids used to dissolve gold.
- Aquatic Ecotoxicity
- The study of how chemicals affect the water environment and the organisms living there.
- Aqueous Solubility
- The maximum concentration of a chemical that will dissolve in pure water at a reference temperature.
- Aqueous Solution
- A solution in which water is the dissolving medium or solvent.
- Ar
- An inert gas that makes up about 1% of the atmosphere.
- Arene
- A hydrocarbon that contains at least one aromatic ring.
- Argentite
- Naturally occuring Silver Sulphide. An important ore of silver.
- Argentum
- Latin for silver, hence the symbol Ag.
- Arginine
C6H14N4O2 A semiessential or conditionally essential amino acid in mammals. - Argon
- An inert gas that makes up about 1% of the atmosphere.
- Aromatic
- Aromatic compounds have strong, characteristic odors.
- Aromatic Compound
- A compound containing an aromatic ring.
- Aromatic Ring
- An exceptionally stable planar ring of atoms with resonance structures that consist of alternating double and single bonds, e. g. benzene.
- Arsenic
- A brittle, crystalline solid which tarnishes readily in air and burns in oxygen.
- Arsenic III Oxide
As2O3 White crystalline solid, used as an opacifier in glazes. - Arsenic V Oxide
As2O5 White solid. - Arsenical Bronze
- An alloy of copper and arsenic in addition to other metals.
- Arsenical Copper
- An alloy of copper and arsenic in addition to other metals.
- Arsine
- Old name for Hydrogen Arsenide.
- Aryl
- A molecular fragment or group attached to a molecule by an atom that is on an aromatic ring.
- As
- A brittle, crystalline solid which tarnishes readily in air and burns in oxygen.
- As2O3
- Chemical formula for Arsenic III Oxide.
- As2O5
- Chemical formula for Arsenic V Oxide.
- Asbestos
- This description covers a number of fibrous silicate minerals such as calcium magnesium silicate.
- Asbestosis
- Fibrosis of the lungs caused by inhalation of asbestos fibres.
- Ash
- The mineral content of a product remaining after complete combustion.
- AsH3
- Chemical formula for Hydrogen Arsenide.
- Aspartic Acid
- A nonessential amino acid that is abundant in molasses.
- Aspirin
- Common name for Acetyl-Salicyclic Acid.
- Assay
- A quantitative determination of the metal in an ore or alloy.
- Astatine
- The heaviest halogen and radioactive.
- At
- Astatine is heaviest halogen and radioactive.
- Atactic
- A type of polymer chain configuration wherein side groups are randomly positioned on one side of the polymer backbone or the other.
- atm
- An abbreviation of atmosphere.
- Atom
- The smallest particle of an element that can exist and still retain the ordinary chemical properties of that element.
- Atom Percent
- Concentration specification on the basis of the number of moles or atoms of a particular element relative to the total number of moles or atoms of all elements within an alloy.
- Atomic Nucleus
- A tiny, incredibly dense positively charged mass at the heart of the atom - normally abbreviated Nucleus.
- Atomic Number
- The atomic number (Z) of an element is the number of protons each atom of that element has in its nucleus.
- Atomic Orbital
- A wavefunction that describes the behavior of an electron in an atom.
- Atomic Packing Factor
- The fraction of the volume of a unit cell that is occupied by ′hard sphere′ atoms or ions.
- Atomic Radius
- One half the distance between nuclei of atoms of the same element, when the atoms are bound by a single covalent bond or are in a metallic crystal.
- Atomic Theory
- An explanation of chemical properties and processes that assumes that tiny particles called atoms are the ultimate building blocks of matter.
- Atomic weight
- The weighted average mass of the atoms in a naturally occurring element.
- Au
- Gold is a soft metal with a characteristic yellow colour. It is the most malleable and ductile of any element. It is unaffected by air, water, alkalis and acids.
- Aufbau Principle
- An approximate procedure for writing the ground state electronic configuration of atoms.
- Auricupride
Cu3Au A natural alloy of copper and gold. - Aurum
- Latin for gold, hence the symbol Au.
- Austenite
- Face-centered cubic iron; also iron and steel alloys that have the FCC crystal structure.
- Autoclave
- An airtight vessel constructed of thick-walled steel alloy for carrying out chemical reactions under pressure and high temperatures. Auto-claves are used for the industrial processing of composite materials.
- Auto-Ignition Temperature
- Minimum temperature at which the vapour/air mixture over a liquid spontaneously catches fire.
- Autoprotolysis
- Transfer of a hydrogen ion between molecules of the same substance.
- Autoxidation
- Oxidation caused by exposure to air.
- Auxochrome
- A group or substructure in a molecule that influences the intensity of absorption of the molecule.
- Avalanche
- A cumulative ionization process.
- Average Bond Enthalpy
- Average enthalpy change per mole when the same type of bond is broken in the gas phase for many similar substances.
- Avogadros Number
- N = 6.022045x1023 mol-1
- Azeotrope
- A solution that does not change composition when distilled.
- Azobenzene
- Red insoluble crystalline powder.
- B
- Boron is a non-metallic element which occurs in several allotropes.
- B100 Biodiesel
- 100% biodiesel.
- B20 Biodiesel
- A blend of biodiesel fuel with petroleum-based diesel where 20% of the volume is biodiesel.
- Ba
- Elemental barium does not occur naturally although it has an abundance within the earth’s crust of 500 ppm.
- Babbitt
- A soft antifriction metal used to line bearings.
- Back Titration
- Determining the concentration of an analyte by reacting it with a known number of moles of excess reagent.
- BaCO3
- Chemical formula for Barium Carbonate.
- Baekeland, Leo Hendrik
- Belgian-born American chemist who invented Velox photographic paper and Bakelite.
- Bakelite
- The first industrial thermoset plastic.
- Bakers Salt
- Old name for Ammonium Carbonate.
- Balanced Equation
- A description of a chemical reaction that gives the chemical formulas of the reactants and the products of the reaction, with coefficients introduced so that the number of each type of atom and the total charge is unchanged by the reaction.
- Balmer Series
- A series of lines in the emission spectrum of hydrogen that involve transitions to the n=2 state from states with n>2.
- Bamboo
- A natural material with a great strength to weight ratio. It was used in the early construction of aircraft wings and fuselages.
- Barite
- Most commonly found mineral of Barium Sulphate.
- Barium
- Elemental barium does not occur naturally although it has an abundance within the earth’s crust of 500 ppm.
- Barium Carbonate
BaCO3 Chemical used in rat poison, bricks, ceramic glazes and cement. - Barium Dioxide
- A white toxic powder obtained by heating barium oxide in air.
- Barium Monoxide
- An oxide of barium; a whitish toxic powder.
- Barium Oxide
- An oxide of barium; a whitish toxic powder.
- Barium Peroxide
- A white toxic powder obtained by heating barium oxide in air.
- Barium Protoxide
- An oxide of barium; a whitish toxic powder.
- Barium Sulphate
BaSO4 A white insoluble solid used as a pigment and filler in plastics. Most commonly found as the mineral Barite. - Barium White
- An ancient name for Barium Sulphate.
- Baryta
- Any of several compounds of barium.
- Base
- Substance which gives off hydroxide ions (OH-) in solution. In the expression xy, x is called the base and y is the exponent.
- Base Oil
- A liquid having a suitable boiling range and viscosity for use in lubricating oils.
- BaSO4
- Chemical formula for Barium Sulphate.
- Bath Metal
- A cheap bronze made with 21 parts copper and 5 parts zinc. The same as pinchbeck.
- Battery
- A device for converting chemical energy into electrical energy.
- Battery Acid
- A solution of approximately 6M sulfuric acid used in the lead storage battery.
- Bauxite
- An ore of aluminum consisting of moderately pure hydrated alumina.
- Bay Salt
- Alternative name for Sodium Chloride.
- bcc
- Abbreviation of body centred cubic. About 15% of all the elements crystallize into this structure.
- Be
- Beryllium is a light and lustrous metal that is resistant to attack by air or water, even at elevated temperatures
- Be3N2
- Chemical formula of Beryllium Nitride.
- BeBr2
- Chemical formula of Beryllium Bromide.
- BeCl2
- Chemical formula of Beryllium Chloride.
- BeF2
- Chemical formula of Beryllium Fluoride.
- BeI2
- Chemical formula of Beryllium Iodide.
- Bell Metal
- Copper tin alloy with much higher tin content than conventional bronze in order to make it hard and sonorous. It is too brittle to be used for many other applications.
- Benzaldehyde
C6H5CHO A colourless to yellow liquid with an almon like odour. Also known as Benzoic Aldehyde, Almond Artificial Essential Oil, Benzenecarbonal, Benzene Carboxaldehyde and Oil of Bitter Almond. - Benzene
- An aromatic hydrocarbon used in the manufacture of many organic compounds.
- Benzene Carboxaldehyde
- Alternative name for Benzaldehyde.
- Benzenecarbonal
- Alternative name for Benzaldehyde.
- Benzoic Acid
C6H5.COOH Used as a fruit preservative. At room temperature it is a colourless solid forming glistening needles and plates, sublimes easily and is volatile in steam. - Benzoic Aldehyde
- Alternative name for Benzaldehyde.
- Benzoin
C14H12O2 An organic compound consisting of an ethylene bridge flanked by phenyl groups and with a hydroxyl and a ketone functional group. It comes as off-white crystals, with a light camphor odor. - BeO
- Chemical formula of Beryllium Oxide.
- Berkelium
- Element with an atomic number of 97.
- Beryllia
- Alternative name for Beryllium Oxide.
- Beryllia Ceramic
- Alternative name for Beryllium Oxide.
- Beryllium
- Beryllium is a light and lustrous metal that is resistant to attack by air or water, even at elevated temperatures
- Beryllium Bromide
BeBr2 Hygroscopic and dissolves readily in water. - Beryllium Chloride
BeCl2 White crystalline substance that reacts vigorously and exothermically with water with the evolution of acidic, steamy hydrogen chloride gas. It attacks many metals in presence of water. - Beryllium Copper
- Heat treatable copper-beryllium alloy of high strength and hardness. Used for making springs and non-sparking tools.
- Beryllium Fluoride
BeF2 A crystalline solid, the principal precursor for the manufacture of beryllium metal. - Beryllium Hydroxide
Be(OH)2 A white solid. One of only a few amphoteric metal hydroxides. - Beryllium Iodide
BeI2 Colourless needle-like crystals that are very hygroscopic and reacts violently with water, forming hydroiodic acid. - Beryllium Nitride
Be3N2 A common component of refractory ceramics. - Beryllium Oxide
BeO White crystalline oxide that when sintered is very stable and has ceramic characteristics. - Beryllium Telluride
BeTe A crystalline solid that is a semiconductor with a large energy gap of around 3 eV. - BeTe
- Chemical formula of Beryllium Telluride.
- Bi
- Bismuth is a brittle metal which is silvery in colour with a pink tinge.
- Bidentate
- A ligand that has two "teeth" or atoms that coordinate directly to the central atom in a complex.
- Bifunctional Monomer
- A monomer unit that has two active bonding positions.
- Bihexyl
- Another name for Dodecane.
- Billon
- An alloy of copper and silver with more than 50% copper.
- Bimolecular Step
- Two species are reacting and form the transition state.
- Binary Compound
- A compound that contains two different elements.
- Biochemistry
- The chemistry of living things, including the structure and function of biological molecules and the mechanism and products of their reactions.
- Biodiesel
- Diesel fuel derived from renewable lipid feedstocks, such as vegetable oils and animal fats.
- Biodiesel B100
- 100% (neat) biodiesel. The mono alkyl esters of long chain fatty acids derived from renewable lipid feedstocks, such as vegetable oils and animal fats, diesel engines
- Biodiesel B20
- A blend of biodiesel fuel with petroleum-based diesel where 20% of the volume is biodiesel.
- Biosensor
- Either a sensor to detect a biological substance or a sensor which incorporates the use of biological molecules such as antibodies or enzymes.
- Biotin
- Commonly known as vitamin H.
- Bismuth
- Bismuth is a brittle metal which is silvery in colour with a pink tinge.
- Bismuth Chloride
BiCl3 A water soluble crystalline source of bismuth. - Bismuth Germanate
Bi4Ge3O12 Used in detectors in particle physics and nuclear medicine. - Bismuth Subcarbonate
Bi2O2(CO3) Chemical compound of bismuth containing both oxide and carbonate. - Bismuth Subgallate
C7H5BiO6 Used in medicine as an internal deodorant. - Bittern
- Waste solution of magnesium salts and bromides from the preparation of salt from sea-water by evaporation.
- Bitumen
- A name used to describe many different mixtures of hydrocarbons.
- Bk
- Berkelium is an element with an atomic number of 97.
- Black, Joseph
- Scottish chemist who laid the foundations for thermodynamics.
- Black Lead
- Natural crystalline form of carbon, used to make vessels that resist high temperatures and in making pencils.
- Blackett, Patrick Maynard Stuart
- English chemist who developed the cloud chamber.
- Blast Furnace
- A vertical shaft type furnace used for reducing iron ore to pig iron when cast or hot metal for further melting. This product is used in an open hearth or basic oxygen furnaces for production of steel.
- Bleach
- A dilute solution of sodium hypochlorite or calcium hypochlorite which kills bacteria and destroys coloured organic materials by oxidizing them.
- Blind Reference Oil
- A reference oil, the identity of which is unknown by the test facility.
- Block Copolymer
- A linear copolymer in which identical mer units are clustered in blocks along the molecular chain.
- Blue Vitriol
- An old fashioned name for hydrated copper sulphate.
- Body Centred Cubic
- About 15% of elements crystallize with a body centred cubic structure.
- Boiling Point
- The temperature at which the vapour pressure of a liquid is equal to the external pressure on the liquid.
- Boiling Point Elevation
- The boiling point of a solution is higher than the boiling point of the pure solvent.
- Bond Energy
- The energy required to break a given chemical bond.
- Bond Enthalpy
- Enthalpy change per mole when a bond is broken in the gas phase for a particular substance.
- Bond Length
- The average distance between the nuclei of two bonded atoms in a stable molecule.
- Bond Order
- In Lewis structures, the number of electron pairs shared by two atoms.
- Bond Strength
- Some measure of how difficult it is to break a chemical bond, for example, a bond energy or a bond enthalpy.
- Bonding Energy
- The energy required to separate two atoms that are chemically bonded to each other.
- Bone
- Primarily based on phosphate and carbonate.
- Bone Black
- An impure animal charcoal prepared from bones and blood.
- Boron
- Boron is a non-metallic element which occurs in several allotropes.
- Boyle, Robert
- Known for that scientific law named after him.
- bp
- Abbreviation of boiling point, the temperature at which the vapour pressure of a liquid is equal to the external pressure on the liquid.
- Bq
- An abbreviation of Becquerel. One Becquerel is that quantity of a radioactive material that will have 1 transformations in one second.
- Br
- Bromine is an element in the halogen group.
- Bragg′s Law
- A relationship that stipulates the condition for diffraction by a set of crystallographic planes.
- Branched Polymer
- A polymer having a molecular structure of secondary chains that extend from the primary chains.
- Brimstone
- Ancient name for Sulphur.
- Brominated Flame Retardants
- A group of chemicals used in plastics and textiles to give flame retardant properties.
- Bromine
- An element in the halogen group.
- Bromoethane
C2H5Br A colourless volatile liquid that has an ether-like odour. - Bromomethane
CH3Br A colorless, nonflammable gas with no distinctive smell. - Brösted Acid
- A material that gives up hydrogen ions in a chemical reaction.
- Brösted Base
- A material that accepts hydrogen ions in a chemical reaction.
- Buckminsterfullerene
C60 A form of carbon consisting of 60 carbon atoms bound together to make a roughly spherical "buckyball". - Buckyball
- A form of carbon consisting of 60 carbon atoms bound together to make a roughly spherical buckyball.
- Buffer Solutions
- Solutions that resist changes in their pH, even when small amounts of acid or base are added.
- Bunsen Burner
- A gas burner with adjustable air intake, commonly used in laboratories.
- Bunsen, Robert Wilhelm
- Introduced the bunsen burner.
- Buret
- A cylindrical glass tube closed by a stopcock on one end and open on the other, with volume gradations marked on the barrel of the tube, used to precisely dispense a measured amount of a liquid.
- Burette
- A cylindrical glass tube closed by a stopcock on one end and open on the other, with volume gradations marked on the barrel of the tube, used to precisely dispense a measured amount of a liquid.
- Burgess Vector
- A vector that denotes the magnitude and direction of lattice distortion associated with a dislocation.
- Butane
C4H10 An alkane hydrocarbon. Commonly used in compressed form for portable heaters and cookers. - Butanol
- An alcohol containing four carbon atoms.
- Butene
C4H8 A colourless gas that is present in crude oil as a minor constituent in quantities that are too small for viable extraction. - Butter of Zinc
- An old name for Zinc Chloride.
- Butyl Alcohol
- Alternative name for Butanol.
- C
- Carbon occurs naturally in two allotropic forms, namely graphite and diamond.
- C10H16
- Chemical formula for Adamantane.
- C10H22
- Chemical formula for Decane.
- C11H24
- Chemical formula for Undecane.
- C12H10
- Chemical formula of Acenaphthene.
- C12H10N2
- Chemical formula for Azobenzene.
- C12H26
- Chemical formula for Dodecane.
- C12H6O2
- Chemical formula for Acenaphthoquinone.
- C12H8
- Chemical formula for Acenaphthylene.
- C13H9N
- Chemical formula for Acridine.
- C14H10
- Chemical formula for Anthracene.
- C14H12O2
- Chemical formula for Benzoin.
- C14H8O
- Chemical formula for Anthraquinone.
- C15H24
- Chemical formula for Zingiberene.
- C16H32
- Chemical formula for Cetene.
- C19H22N2OS
- Chemical formula for Acepromazine.
- C20H30O2
- Chemical formula for Abietic Acid.
- C21H28O5
- Chemical formula for Aldosterone.
- C2H2
- Chemical formula for Acetylene.
- C2H3N
- Chemical formula for Acetonitrile.
- C2H3OCl
- Chemical formula for Acetyl Chloride.
- C2H4O
- Chemical formula for Acetaldehyde.
- C2H5Br
- Chemical formula for Bromoethane.
- C2H5Cl
- Chemical formula for Chloroethane.
- C2H5OH
- Chemical formula for ethanol.
- C2H5ON
- Chemical formula for Acetamide.
- C2H6
- Chemical formula for Ethane.
- C2HCl3
- Chemical formula for Trichlorethene.
- C2N2
- Chemical formula for Cyanogen.
- C3H3ClO
- Chemical formula for Acryloyl Chloride.
- C3H3N
- Chemical formula for Acrylonitrile.
- C3H4O
- Chemical formula for Acrolein.
- C3H4O2
- Chemical formula for Acrylic Acid.
- C3H5N3O9
- Chemical formula for Nitroglycerine.
- C3H5NO
- Chemical formula for Acrylamide.
- C3H6
- Chemical formula for Propene.
- C3H6O
- Chemical formula for acetone.
- C3H6O2
- Chemical formula for Methyl Acetate.
- C3H7NO2
- Chemical formula for Alanine.
- C3H7OH
- Chemical formula for Propanol.
- C3H8
- Chemical formula for Propane.
- C3H8O3
- Chemical formula for Glycerol.
- C4H10
- Chemical formula for butane.
- C4H12N2
- Chemical formula for Putrescine.
- C4H6O3
- Chemical formula for Acetic Anhydride.
- C4H6O5
- Another name for Hydroxybutanedioic Acid.
- C4H9OH
- Chemical formula for Butanol.
- C56H68Cl4CuN16S4
- Chemical formula for Alcian Blue.
- C5H11NO2
- Chemical formula for Amyl Nitrite.
- C5H11OH
- Chemical formula for Pentanol.
- C5H12
- Chemical formula for pentane.
- C5H8O2
- Chemical formula for Angelic Acid.
- C60
- Buckminsterfullerene formed from 60 carbon atoms.
- C6H10O4
- Chemical formula for Adipic Acid.
- C6H14
- Chemical formula for Hexane.
- C6H14N4O2
- Chemical formula for Arginine.
- C6H5CHO
- Chemical formula for Benzaldehyde.
- C6H5 COOH
- Chemical formula for Benzoic Acid.
- C6H5NO2
- Chemical formula for nitrobenzene.
- C6H5OH
- Chemical formula for Phenol.
- C6H6
- Chemical formula for benzene, an aromatic hydrocarbon used in the manufacture of many organic compounds.
- C6H6O
- The chemical formula for phenol, a strong disinfectant.
- C6H7N
- Chemical formula for Aniline.
- C6H8Cl2O2
- Chemical formula for Adipoyl Chloride.
- C7H16
- Chemical formula for heptane.
- C7H8
- Chemical formula for toluene.
- C7H8O
- Chemical formula for Anisole.
- C8H10N4O2
- A substance found in tea, coffee, and cola that acts as a stimulant.
- C8H11N5O3
- Chemical formula for Aciclovir.
- C8H18
- Flammable liquid compounds found in petroleum and natural gas.
- C8H8O
- Chemical formula for Acetophenone.
- C8H9NO2
- Chemical formula for Acetaminophen.
- C8H9ON
- Chemical formula for Acetanilide.
- C9H20
- Chemical formula for Nonane.
- Ca
- Calcium is one of the most abundant metal elements on Earth (41000 ppm).
- CaC2
- Chemical formula for Calcium Carbide.
- CaCl2
- Chemical formula for Calcium Chloride
- CaCO3
- Chemical formula for Calcium Carbonate.
- Cadmium
- A white metallic element.
- Cadmium Oxide
- Commonly used in glasses, plastics, ceramics and porcelain enamels as a coloring agent for reds, oranges, and yellows.
- Cadmium Sulphate
CdSO4 Colourless, odourless crystals that are freely soluble. - Cadmium Sulphide
CdS Found as the mineral greenockite, it is used together with selenium to produce strong reds and yellows. - Caesium
- A soft metal which is often liquid at room temperature due to its relatively low melting point (28.5°C).
- Caesium Bromide
CsBr White crystalline solid. - Caesium Chloride
CsCl White crystalline solid. - Caesium Fluoride
CsF White crystalline solid. - Caesium Hydride
CsH White crystalline solid. - Caesium Iodide
CsI White crystalline solid. - Caesium Oxide
Cs2O Yellow to orange crystalline solid. - Caesium Peroxide
Cs2O2 Yellow crystalline solid. - Caesium Sulphide
Cs2S White to pale yellow crystalline solid. - Caesium Superoxide
CsO2 Yellow to orange crystalline solid. - Caffeine
- A substance found in tea, coffee, and cola that acts as a stimulant. It is extremely soluble in supercritical fluid carbon dioxide and somewhat soluble in water; aqueous solutions of caffeine quickly break down.
- Calamine Brass
- Brass produced by a particular alloying technique using calamine (a zinc ore) rather than metallic zinc.
- Calcination
- A high-temperature reaction whereby one solid material dissociates to form a gas and another solid.
- Calcium
- One of the most abundant metal elements on Earth (41000 ppm).
- Calcium Carbide
CaC2 Usually formed by fusing lime and hard coal in a furnace. - Calcium Carbonate
CaCO3 A white insoluble solid, occuring naturally as chalk, limestone, marble and calcite. - Calcium Chloride
CaCl2 Absorbs moisture from the atmosphere and is used for drying gases. - Calcium Hypochlorite
CaCl(OCl) More commonly known as bleaching powder. - Calcium Oxide
CaO Also know as Quicklime. - Calcium Sulphate
CaSO4 Used to make plaster of paris and plaster. - Californium
- A man-made element with an atomic number of 98.
- Calomel
- Another name for Mercury I Chloride.
- Calutron
- A device that separates isotopes by ionizing the sample.
- CaO
- Chemical formula for Calcium Oxide.
- Carbide
- The old abbreviated name for calcium carbide.
- Carbohydrate
- A class of organic compounds including sugars and starches.
- Carbolic Acid
- Also known as phenol, it is used as a strong disinfectant.
- Carbon
- Occurs naturally in two allotropic forms, namely graphite and diamond.
- Carbon Bisulphide
- Alternative name for Carbon Disulphide.
- Carbon Dioxide
- A heavy, colourless gas that is the fourth most abundant constituent of dry air, comprising 0.033% of the total.
- Carbon Disulphide
- Also known as Carbon Bisulphide used as a solvent in the vulcanization of rubber.
- Carbon Hydride Nitride
- Alternative name for Hydrogen Cyanide.
- Carbon Monoxide
- A colourless gas that is very poisonous as it combines with the haemoglobin in blood forming a stable compound so reducing the ability to carry oxygen.
- Carbon Tetrachloride
- Colourless liquid with a sweet smell used as a solvent.
- Carbon Tetrafluoride
- Alternative name for Tetrafluoromethane.
- Carbonado
- Carbon that has metamorphosed into its diamond phase but remains black.
- Carbonate
- An inorganic ion with a charge of -2, containing carbon bound directly to three oxygens in a in a flat triangular arrangement.
- Carbonic Acid
H2CO3 A weak acid formed by carbon dioxide dissolved in water. - Carbonic Oxide
- Old name for Carbon Monoxide.
- Carboxamide
NH2CONH2 More commonly known as Urea, the main nitrogenous excretion of most animals. It has the distinction of being the first organic compound to have been made in a laboratory (1828). Urea is used in the manufacture of ammonia and carbon dioxide. - Carboxylic Acid
- A compound with molecules containing a carboxylic acid group -COOH.
- Carboy
- A very large bottle.
- Carburetted Hydrogen
- Old name for Methane.
- Carcinogens
- Substances known to cause cancer.
- Carotene
- Carotene is an unsaturated hydrocarbon pigment found in many plants. Carotene is the basic building block of vitamin A.
- CaSO4
- Chemical formula for Calcium Sulphate.
- Cassiterite
- Dark coloured mineral that is an important ore of Tin.
- Catalyst
- Substance that speeds up a chemical process without actually changing the products of reaction.
- Catalytic Converter
- An air pollution abatement device that removes pollutants from motor vehicle exhaust, either by oxidizing them into carbon dioxide and water or reducing them to nitrogen.
- Catalytic Cracking
- The use of a catalyst to break down the molecules of the high boiling temperature fractions of crude oil.
- Cathode
- Electrode where electrons are gained (reduction) in redox reactions.
- Cathodic Protection
- A means of corrosion prevention.
- Cations
- Ion with a positive charge.
- Cauk
- Old name for Barium Sulphate.
- Caustic Potash
- Old fashioned name for Potassium Hydroxide.
- Caustic Soda
- Alternative name for Sodium Hydroxide.
- Cavendish, Henry
- English physicist and chemist, discovered hydrogen.
- Cawk
- Old name for Barium Sulphate.
- CCl3F
- Chemical formula for Trichlorofluoromethane.
- CCl4
- Chemical formula for Carbon Tetrachloride.
- Cd
- Cadmium is a white metallic element.
- CdS
- Chemical formula for cadmium sulphide.
- CdSO4
- Chemical formula for Cadmium Sulphate.
- Ce
- Cerium is a reactive grey metal and is one of the most abundant of the lanthanide group of metals.
- Cellophane
- Cellophane is a thin, transparent, waterproof, protective film that is used in many types of packaging.
- Cellulose
- A polysaccharide made of linked glucose molecules that strengthens the cell walls of most plants.
- Cellulosic Ethanol
- Ethanol made from agricultural refuse, grass, wood, municipal waste and a variety of feedstock, which is less expensive and more available than just corn.
- Cement
- A substance that can be used to build together aggregates of sand or stone into a cohesive structure. May be a single compound or a mixture. May be hydraulic set, air set or chemical set.
- CeO2
- Chemical formula for Cerium Oxide.
- Ceramic
- Inorganic, nonmetalllic products for which the interatomic bonding is predominantly ionic.
- Ceric Oxide
- Another name for Cerium Oxide.
- Cerium
- A reactive grey metal and is one of the most abundant of the lanthanide group of metals.
- Cerium Oxide
CeO2 The oxide of the rare earth element cerium. Cerium oxide usually appears as a yellow powder. It is insoluble in water and moderately soluble in strong mineral acids. Used alone or together with other substances as a polishing agent for glass. - Cermet
- A composite material consisting of a combination of ceramic and metallic materials.
- Cerussite
- Mineral form of Lead II Carbonate.
- Cetane Index
- A calculated value, derived from fuel density and volatility, giving a reasonably close approximation to cetane number.
- Cetane Number
- A percentage indicating the ignition quality of diesel fuels.
- Cetene
C16H32 An oily hydrocarbon of the ethylene series, obtained from spermaceti. - Cf
- Californium is a man-made element with an atomic number of 98.
- CF4
- Chemical formula for Tetrafluoromethane.
- CH2Cl2
- Chemical formula for Dichloromethane.
- CH2O2
- Chemical formula for for Methanoic Acid.
- CH3Br
- Chemical formula for Bromomethane.
- CH3CH2NH2
- Chemical formula for Ethylamine.
- CH3Cl
- Chemical formula for Chloromethane.
- CH3COOC6H4COOH
- Chemical formula for Acetyl-Salicyclic Acid.
- CH3COOCH2CH3
- Chemical formula for Ethyl Acetate.
- CH3OH
- A colourless liquid also known as methyl alcohol.
- CH4
- The chemical formula for methane, the first alkane.
- CH4O
- Chemical formula for Methyl Alcohol.
- Chalk
- Common form of Calcium Carbonate.
- Change of State
- The change in a substance between solid and liquid or between liquid and gas.
- Characteristic X-ray
- An X-ray having a unique energy that is emitted by an atom during its de-energization after ionization of one of its electrons.
- Charcoal
- Used to describe different forms of carbon. Formed by heating vegetable or animal matter in the absence of air.
- Charged
- Possessing a net negative or positive charge.
- CHCl3
- Chemical formula for chloroform.
- Chelate
- A stable complex of a metal with one or more polydentate ligands.
- Chelating Agent
- A ligand that binds to a metal using more than one atom; a polydentate ligand.
- Chemical
- 1. of or pertaining to chemistry. 2. a substance.
- Chemical Analysis
- Determination of the composition of a sample.
- Chemical Bond
- A chemical bond is a strong attraction between two or more atoms.
- Chemical Energy
- Energy stored in the bonds of atoms and molecules eg coal, petrol, biomass.
- Chemical Equation
- A compact notation for describing a chemical change.
- Chemical Formula
- A representation of a chemical substance that uses chemical symbols to denote the constituent atoms, and subscripts to indicate the relative numbers of atoms of each type.
- Chemical Set Cement
- A cement that sets through reaction or precipitation.
- Chemical Stability
- The tendency of a substance or mixture to resist chemical change.
- Chemiluminescence
- A chemical reaction that releases energy as electromagnetic radiation.
- Chile Nitre
- Another name for Sodium Nitrate.
- Chinese Silver
- An alloy used for jewellery, 58% copper, 17.5% zinc, 11.5% nickel, 11% cobalt, and 2% silver.
- Chinese White
- The old name for Zinc Oxide.
- Chlorane
- Alternative name for Hydrogen Chloride.
- Chlorination
- The application of chlorine to drinking water, sewage, or industrial waste to disinfect or to oxidize undesirable compounds.
- Chlorine
- A greenish yellow gas and second in the halogen group.
- Chloroethane
C2H5Cl A colorless, flammable gas or refrigerated liquid with a faintly sweet odour. - Chloroform
- Volatile colourless heavy liquid used as an anaesthetic and solvent.
- Chlorohydric Acid
- Alternative name for Hydrochloric Acid.
- Chloromethane
CH3Cl A colourless extremely flammable gas with a slightly sweet odor. Once commonly used as a refrigerant. - Chromatography
- A method for separating mixtures based on differences in the speed at which they migrate over or through a stationary phase.
- Chrome Green
- Alternative name for Chromium Oxide.
- Chrome Yellow
- An old name for Lead II Chromate IV.
- Chromel
- An alloy of nickel with about 10% chromium, used with Alumel in K-type thermocouples.
- Chromic Oxide
- Alternative name for Chromium Oxide.
- Chromium
- A bright, blue/white metal with excellent corrosion resistance.
- Chromium Dioxide
CrO2 A black crystalline solid. - Chromium IV Oxide
- Alternative name for Chromium Dioxide.
- Chromium Oxide
Cr2O3 The only stable oxide of chromium. It is a bright to dark green crystalline powder insoluble in alkalis and acids. - Chromium VI Oxide
CrO3 Highly poisonous. - Chromophore
- A group or substructure on a molecule that is responsible for the absorption of light.
- Cl
- Chlorine is a greenish yellow gas and second in the halogen group.
- Cm
- Curium is a man-made radioactive element.
- CNG
- Abbreviation of Compressed Natural Gas.
- Co
- Cobalt is a hard, grey metal which is ferromagnetic.
- CO
- Chemical formula for Carbon Monoxide.
- CO2
- Chemical formula for Carbon Dioxide.
- Co2O3
- Chemical formula for Cobalt III Oxide.
- Coal
- A fossil fuel which is made mostly of carbon. It is formed from plants that grew around 150 million years ago.
- Coal Tar
- A dark brown to black cementitious material produced by the destructive distillation of bituminous coal.
- Cobalt
- A hard, grey metal which is ferromagnetic.
- Cobalt Dichloride
- Alternative name for Cobalt II Chloride.
- Cobalt II Bromide
CoBr2 Green crystals, used as a catalyst in the oxidation of some organic compounds. - Cobalt II Chloride
CoCl2 Used as an indicator for water as there is a dramatic colour change from CoCl2 which is blue to CoCl2·6H2O which is a deep rose colour. - Cobalt II Nitrate
Co(NO3)2 A red crystalline solid with high solubility of cobalt nitrate makes it a common source of cobalt in metal-organic frameworks and polymers. Deliquescent in moist air. - Cobalt II Oxide
CoO Olive green to red crystals or greyish or black powder used in ceramics to create blue coloured glazes. - Cobalt III Oxide
Co2O3 A black substance obtained by adding cobalt II nitrate to an aqueous solution of sodium hypochlorite. - Cobalt Monoxide
- Alternative name for Cobalt II Oxide.
- Cobalt Sesquioxide
- Alternative name for Cobalt III Oxide.
- Cobalt Trioxide
- Alternative name for Cobalt III Oxide.
- Cobaltic Oxide
- Alternative name for Cobalt III Oxide.
- Cobaltous Chloride
- Alternative name for Cobalt II Chloride.
- Cobaltous Monoxide
- Alternative name for Cobalt II Oxide.
- Cobaltous Nitrate
- Alternative name for Cobalt II Nitrate.
- Cobaltous Oxide
- Alternative name for Cobalt II Oxide.
- CoBr2
- Chemical formula for Cobalt II Bromide.
- CoCl2
- Chemical formula for Cobalt II Chloride.
- Coke
- A hard, dry substance containing carbon that is produced by heating bituminous coal to a very high temperature in the absence of air.
- Colligative Properties
- Properties of a solution that depend only on the number of particles dissolved in it, not the properties of the particles themselves.
- Collision Frequency
- The average number of collisions that a molecule undergoes each second.
- Collision Theory
- A theory that explains reaction rates in terms of collisions between reactant molecules.
- Colloid
- A heterogeneous mixture composed of tiny particles suspended in another material.
- Columbium
- A name sometimes given to Niobium, a platinum-gray, ductile metal with brilliant luster that is used in alloys, especially stainless steels.
- Column Chromatography
- A method for separating mixtures.
- Columnar Structure
- Coarse structure of parallel columns of grains.
- Combustible
- Substance that can easily be set on fire and that will burn readily or quickly. Flammable.
- Combustion Reaction
- The vigorous and exothermic reaction that takes place between certain substances, particularly organic compounds, and oxygen.
- Common Salt
- Sodium Chloride.
- Complex Ion
- An ion formed by combination of simpler ions or molecules.
- Complexing Agent
- A ligand that binds to a metal ion to form a complex.
- Complexometric Titration
- A titration based on a reaction between a ligand and a metal ion to form a complex.
- Component
- An element or chemical compound that helps make up a material system.
- Compound
- A pure substance which contains two or more different elements chemically bonded together in stoichiometric proportions.
- Compressed Natural Gas
- Natural gas compressed to a volume and density that is practical as a portable fuel supply.
- Computational Chemistry
- A branch of chemistry concerned with the prediction or simulation of chemical properties, structures, or processes using numerical techniques.
- CoN2O6
- Chemical formula for Cobalt II Nitrate.
- Concentrate
- To increase the amount of substance present in a unit amount of mixture.
- Concentration
- The amount of substance in a specified space.
- Concentration Cell
- A voltaic cell in which both compartments contain the same components, but at different concentrations.
- Concrete
- Building material made from cement, sand, stone and water.
- Condensation Polymerization
- The formation of polymers by an intermolecular reaction involving at least two monomer species.
- Congruent Transformation
- A transformation of one phase to another that does not involve any change in composition.
- Conjugate Acid
- A substance which can lose a H+ ion to form a base.
- Conjugate Base
- A substance which can gain a H+ ion to form an acid.
- Constantan
- An alloy of 40% nickel and 60% copper, with a high volume resistivity and almost negligible temperature coefficient. Used with copper in T-type thermocouples.
- Contaminant
- Any foreign or unwanted substance that can have a negative effect on system operation, life or reliability.
- Continuous Spectrum
- A plot of the relative absorbance or intensity of emitted light vs. wavelength or frequency that shows a smooth variation, rather than a series of sharp peaks or bands.
- CoO
- Chemical formula for Cobalt II Oxide.
- COOH
- Carboxylic acid group.
- Coordination Number
- The number of atomic or ionic nearest neighbours.
- Copolymer
- A polymer that consists of two or more dissimilar mer units in combination along its molecular chains.
- Copper
- Noted for being ductile and having good electrical and thermal conductivity. It forms the basis of a number of alloys.
- Copper I Bromide
CuBr Yellowish green or white crystalline solid. - Copper I Chloride
CuCl White crystalline solid. Turns green in moist air. - Copper I Iodide
CuI White crystalline solid. - Copper I Oxide
Cu2O A red powder. - Copper I Sulphide
Cu2S Yellow, red, or brown crystalline solid. - Copper II Bromide
CuBr2 Black crystalline solid. Reacts violently with potassium. - Copper II Carbonate
CuCO3 Green or blue powder forming most of the patina one sees on weathered brass, bronze, and copper. Used as a pigment. - Copper II Hydroxide
Cu(OH)2 Used as a fungicide. - Copper II Oxide
CuO A black-brown crystalline solid. - Copper II Sulphide
CuS Blue-black or black crystalline solid. - Copper Sulphate
CuSO4 A water soluble salt used in copper plating. - Copperas
- The mineral form of Iron II Sulphate.
- Core Electron
- Electrons occupying completely filled shells under the valence shell.
- Cork
- Outer waterproof layer covering most trees and shrubs. The cork material used in flooring and for it′s properties is from the tree Quercus Suber.
- Corrosion
- Deteriorative loss of a metal as a result of dissolution environmental reactions.
- Corrosive
- Having the power to dissolve. Can burn and destroy living tissue.
- Corrosive Sublimate
- Another name for Mercury II Chloride.
- Coulombic Force
- A force between charged particles, such as ions.
- Covalent Bond
- Describes the mutual electrostatic attraction of two or more adjacent nuclei for a shared pair of electrons which occupy the same molecular energy level.
- Covalent Radius
- The radius of atoms obtained from covalent bond lengths.
- Cr
- Chromium is a bright, blue/white metal with excellent corrosion resistance.
- Cr2O3
- Chemical formula for Chromium Oxide.
- Cracking
- The thermal decomposition of the molecules of high molecular mass organic compounds to produce molecules of compounds of lower molecular mass.
- Critical Temperature
- The temperature at the critical point.
- CrO2
- Chemical formula for Chromium Dioxide.
- Crosslinked Polymer
- A polymer in which adjacent linear molecular chains are joined at various positions by covalent bonds.
- Crown Glass
- A silicate glass containing oxides of sodium and potassium, used in compound lenses and spectacles; harder than flint glass, with low index and low dispersion.
- Crown Gold
- 2 carats of alloy (usually copper sometimes silver) and 22 carats of gold so called from the gold crown of 1526 which used this alloy.
- Cryogenic Gas
- A gas that has been liquified by lowering the temperature, usually to a temperature under about -100°C.
- Crystal
- A material in which the atoms are arranged in a definite geometric pattern.
- Crystal Structure
- For crystalline materials, the manner in which atoms or ions are arrayed in space. It is defined in terms of the unit cell geometry and the atom positions within the cell.
- Crystal System
- A scheme by which crystal structures are classified according to unit cell geometry.
- Crystalline
- The state of a solid material characterized by a periodic and repeating three-dimensional arrays of atoms, ions, or molecules.
- Crystallite
- A region within a crystalline polymer in which all the molecular chains are ordered and aligned.
- Crystallization
- Act or process of forming crystals or bodies by elements or compounds solidifying.
- Crystals of Silver
- Old name for Silver Nitrate.
- Cs
- A soft metal which is often liquid at room temperature due to its relatively low melting point (28.5°C).
- CS2
- Chemical formula for carbon disulphide.
- Cs2O
- Chemical formula for Caesium Oxide.
- Cs2O2
- Chemical formula for Caesium Peroxide.
- Cs2S
- Chemical formula for Caesium Sulphide.
- CsBr
- Chemical formula for Caesium Bromide.
- CsCl
- Chemical formula for Caesium Chloride.
- CsF
- Chemical formula for Caesium Fluoride.
- CsH
- Chemical formula for Caesium Hydride.
- CsI
- Chemical formula for Caesium Iodide.
- CsO2
- Chemical formula for Caesium Superoxide.
- Cu
- Copper is a reddish coloured metal which is malleable and ductile. It has excellent thermal and electrical conductivities and good corrosion resistance.
- Cu2O
- Chemical formula for Copper I Oxide.
- Cu2S
- Chemical formula for Copper I Sulphide.
- Cubic Nitre
- Name for the crystallised form of Sodium Nitrate.
- CuBr
- Chemical formula for Copper I Bromide.
- CuBr2
- Chemical formula for Copper II Bromide.
- CuCl
- Chemical formula for Copper I Chloride.
- CuCO3
- Chemical formula for Copper II Carbonate.
- CuI
- Chemical formula for Copper I Iodide.
- Cunife
- An alloy of copper, nickel, iron, and in some cases cobalt.
- CuO
- Chemical formula for Copper II Oxide.
- Cupric Bromide
- Old name for Copper II Bromide.
- Cupronickel
- An alloy of copper and nickel that is resistant to corrosion.
- Cuprum
- The old name for Copper and from where the chemical symbol Cu was derived.
- Cure
- To irreversibly polymerize a thermosetting plastic by subjecting it to a time-temperature profile.
- Curium
- Man-made radioactive element.
- CuS
- Chemical formula for Copper II Sulphide.
- CuSO4
- Chemical formula for Copper Sulphate.
- Cyanocobolamin
- Commonly known as vitamin B12.
- Cyanoethene
- Alternative name for Acrylonitrile.
- Cyanogen
- Colourless very poisonous gas that smells of bitter almonds.
- Cycloalkanes
- Saturated compounds containing only carbon and hydrogen atoms in which the carbon backbone forms a ring structure.
- Cyclon
- Alternative name for Hydrogen Cyanide.
- D2O
- Chemical formula for Heavy Water.
- dalton
- The atomic mass unit is sometimes called the dalton, after John Dalton.
- Dalton, John
- He developed atomic theory that accounts for the law of conservation of mass, law of definite proportions and law of multiple proportions.
- Dalton′s Law of Partial Pressures
- The total pressure of a mixture of gases, which do not interact chemically, is equal to the sum of the partial pressures.
- Damps
- Any dangerous vapours in caves, mines etc.
- Darcets Alloy
- A low melting point alloy.
- Debye
- Unit of dipole moment.
- Decane
C10H22 Decane is one of the components of petrol. Like other alkanes, it is nonpolar and therefore will not dissolve in polar liquids such as water. - Decantation
- To a separate the supernatant liquid from a solid precipitate by pouring the liquid off, being careful that all of the solid remains in the vessel.
- Decoction
- Continuous application of boiling heat to a reaction mixture.
- Decompounded
- Doubly compounded, or composed of three or more substances.
- Decrepitation
- Rapid physical decomposition of some crystals when heated. Characterized by a crackling noise.
- Deflagration
- To cause a substance to burn rapidly, with flame.
- Degas
- Removing air from a liquid, usually by ultrasonic or vacuum methods.
- Degenerate Orbital
- A set of orbitals are said to be degenerate if they all have the same energy.
- Degree of Polymerization
- The average number of mer units per polymer chain molecule.
- Dehydrator
- A separator that removes water from the system fluid.
- Deliquescence
- Deliquescent compounds absorb so much moisture from the air that they dissolve.
- Deliquium
- Change of salt from a solid to a fluid state by contact with air only.
- Denatured Alcohol
- Poison is added to industrial ethanol so that the tax is not charged for industrial usage.
- Dephlegmation
- To remove water from a solution, usually one of an acid or alcohol.
- Dephlogisticated Air
- An old name for oxygen.
- Depuration
- To free from impurities, purify.
- Desalination
- Removal of dissolved salts from seawater.
- Desiccator
- A sealed container in which a drying agent is used to dry material that contains water.
- Desquamation
- The process of removing scaly crusts which form on a surface.
- Detonation
- Any rapid chemical reaction accompanied by noise and often heat and light, e.g., explosions.
- Deuterium
- An isotope of hydrogen that contains one neutron and one proton in its nucleus.
- Devitrification
- The process in which a glass (noncrystalline or vitreous solid) transforms to a crystalline solid.
- Dialuminium Hexachloride
- Alternative name for Aluminium Chloride.
- Dialuminium Trisulphide
- Alternative name for Aluminium Sulphide.
- Dialysis
- The separation of components in a mixture by passing them across a semipermeable membrane.
- Diamond
- A crystalline form of carbon, made of a network of covalent, tetrahedrally bound carbon atoms.
- Diastereomers
- Optical isomers that are not mirror images of each other.
- Diatomic Molecules
- Molecules composed of two atoms eg CO.
- Diazotization
- A reaction that converts an -NH2 group connected to a phenyl ring to a diazonium salt.
- Dicaesium Oxide
- Old name for Caesium Oxide.
- Dicaesium Peroxide
- Old name for Caesium Peroxide.
- Dicaesium Sulphide
- Old name for Caesium Sulphide.
- Dichlorodiethyl Sulphide
(CH2CH2Cl)2S Oily gas used in warfare. Also known as mustard gas or yperite. - Dichloromethane
CH2Cl2 Organic solvent often use to extract organic substances from samples. - Dicobalt Trioxide
- Alternative name for Cobalt III Oxide.
- Didymium
- A mixture of praseodymium and neodymium believed to be an element until 1885.
- Diffusion
- The mixing of two substances caused by random molecular motions.
- Diffusion Rate
- The number of randomly moving molecules that pass through a unit area per second.
- Dihexyl
- Another name for Dodecane.
- Dihydrogen Monoxide
- More commonly known as water.
- Dihydrogen Selenide
- Old name for Hydrogen I Selenide.
- Dilatometer
- A device for measuring volume changes.
- Dilithium Oxide
- Old name for Lithium I Oxide.
- Dilithium Peroxide
- Old name for Lithium I Peroxide.
- Dilute
- Having a relatively low concentration.
- Dilution
- Adding solvent to a solution to lower its concentration.
- Dimercury Dichloride
- Another name for Mercury I Chloride.
- Dimethyl Ketone
- Also known as acetone.
- Dimethylbenzenes
- Alternatively known as Xylol.
- Dipole-Dipole Interaction
- Electrostatic attraction between oppositely charged poles of two or more dipoles.
- Dipotassium Oxide
- Old name for Potassium Oxide.
- Dipotassium Peroxide
- Old name for Potassium Peroxide.
- Discontinuity
- A break in sequence or continuity of anything.
- Disilver Sulphide
- Old name for Silver Sulphide.
- Disinfectant
- A substance that kills or stops the growth of microbes.
- Dislocation
- A linear crystalline defect around which there is an atomic misalignment.
- Disodium Oxide
- Old name for Sodium Oxide.
- Dispersant
- An additive that reduces deposits on oil-wetted surfaces primarily through suspension of particles.
- Dissociation
- Breaking down of a compound into its components.
- Dissolve
- To mix a solid and a liquid to form a solution.
- Dissolved Oxygen
- The amount of oxygen dissolved in a solvent (usually water).
- Distillate
- The vapour collected and condensed from a distillation.
- Distillation
- A process used to separate a liquid from a solution.
- Distillation Per Ascensum
- Distillation with the collecting vessel above the heated vessel.
- Distillation Per Decensum
- Any distillation where the collecting vessel is below the heated vessel.
- Distillation Per Obliquium
- Distillation in a retort used for substances of relatively low vapor pressure and other properties that make distillation difficult.
- Distillation with Addition
- Adding some substance prior to distillation that will aid the process.
- Disulfane
- Old name for Hydrogen Persulphide.
- Divalent
- Binds to two other things: atoms, molecules, ions, or electrons.
- Divalent Anion
- An ion with a charge of -2.
- Divalent Cation
- An ion with a charge of +2.
- Dodecane
C12H26 A thick, oily liquid of the paraffin series. It is used as a solvent, distillation chaser and is also the average component of diesel fuel. - Doping
- The intentional alloying of semiconductor materials with controlled concentrations of donor or acceptor impurities
- Double Bond
- When an atom is bonded to another atom by two sets of electron pairs.
- Double Displacement
- A reaction in which two reactants trade fragments.
- Dry Bulb Thermometer
- A thermometer used to measure the ambient temperature.
- Dry Cell
- A electrolytic cell also known as a Leclanché cell that uses a moist paste rather than a liquid as an electrolyte.
- Dulcification
- Any process in which a caustic substance is rendered less corrosive.
- Duodecane
- Another name for Dodecane.
- Dy
- Dysprosium is a silvery metal of the lanthanide group. It is relatively stable in air, reacts violently with water and dissolves in acids.
- Dynamic Equilibrium
- Equilibrium which includes inertial forces.
- Dynamite
- A blasting explosive, based on nitroglycerine, but much safer to handle than nitroglycerine alone.
- Dysprosium
- A silvery metal of the lanthanide group. It is relatively stable in air, reacts violently with water and dissolves in acids.
- E10 Ethanol
- Ethanol mixture that contains 10% ethanol, 90% unleaded gasoline.
- E85
- Refers to a fuel blend of 85 percent ethanol and 15 percent gasoline.
- E85 Ethanol
- Refers to a fuel blend of 85 percent ethanol and 15 percent gasoline.
- Ebulliometry
- Determination of average molecular weight of a dissolved substance from the boiling point elevation of the solution.
- Ebullition
- The agitating, bubbling action of a liquid that is undergoing rapid, active boiling.
- Effective Nuclear Charge
- The nuclear charge experienced by an electron when other electrons are shielding the nucleus.
- Efflorescent
- Efflorescent substances lose water of crystallization to the air.
- Effusion
- Movement of gas molecules through a small opening.
- Einsteinium
- An artificial radioactive element found in the debris of an H bomb.
- Elastomer
- A polymeric material that may experience large and reversible elastic deformations.
- Electric Dipole Moment
- A measure of the degree of polarity of a polar molecule.
- Electrochemistry
- The study of the interchange of chemical and electrical energy.
- Electrodes
- Device that moves electrons into or out of a solution by conduction.
- Electrokinetic Potential
- Electric potential across all phase boundaries between solids and liquids, also known as the Zeta Potential.
- Electrolysis
- Changing the chemical structure of a compound using electrical energy.
- Electrolyte
- A substance that dissociates fully or partially into ions when dissolved in a solvent, producing a solution that conducts electricity.
- Electrolytic cell
- A cell that uses electrical energy to produce a chemical change that would otherwise not occur spontaneously.
- Electromotive Series
- The electrode potential of a material according to decreasing tendency to release electrons with hydrogen as zero.
- Electron Affinity
- The measure of an atom′s tendency to gain an electron.
- Electron Shell
- A group of electrons which have a common energy level that forms part of the outer structure of an atom.
- Electropositive
- For an atom, having a tendency to release valence electrons.
- Electrostatic Interactions
- Attractions between opposite charges or repulsions between like charges that grow stronger as the charges become closer to each other.
- Electrum
- An alloy of 75% gold and 25% silver along with small quantities of other metals such as copper.
- Element
- A pure substance which cannot be broken down into simpler substances by chemical means.
- Emollient
- A substance added to a formulation that gives it softening ability.
- Empirical Law
- A law strictly based on experiment, which may lack theoretical foundation.
- Emulsion
- A colloid formed from tiny liquid droplets suspended in another, immiscible liquid. E.g. Milk.
- Enantiomers
- Stereoisomers that are nonsuperimposable complete mirror images of each other.
- Endergonic
- Refers to a reaction for which the free energy of the system increases.
- Endothermic
- Reaction that absorbs heat from its surroundings as the reaction proceeds.
- Energy Density
- Characteristic parameter of a battery/electrical power source indicating the amount of electrical energy stored per unit weight or volume.
- Enthalpy
- Change in heat.
- Enthalpy of Atomization
- The change in enthalpy that occurs when one mole of a compound is converted into gaseous atoms.
- Enthalpy of Combustion
- The amount of energy released in burning completely an amount of substance.
- Enthalpy of Fusion
- The enthalpy change that occurs to melt a solid at its melting point.
- Enthalpy of Hydration
- The enthalpy change associated with placing gaseous molecules or ions in water.
- Enthalpy of Neutralization
- The heat released by an acid-base neutralization reaction running at constant pressure.
- Enthalpy of Reaction
- The heat absorbed or released by a chemical reaction running at constant pressure.
- Enthalpy of Solution
- The enthalpy change associated with dissolving a solute in a solvent.
- Enthalpy of Sublimation
- The change in enthalpy when one mole of solid vaporizes to form one mole of gas.
- Enthalpy of Vaporization
- The change in enthalpy when one mole of liquid evaporates to form one mole of gas.
- Entropy
- Measure of the disorder of a system.
- Enzyme
- Protein or protein-based molecules that speed up chemical reactions occurring in living things.
- Equivalence Point
- Occurs when the moles of acid equal the moles of base in a solution.
- Er
- Erbium is a silvery grey metal that is a member of the lanthanide group of elements.
- Erbium
- A silvery grey metal that is a member of the lanthanide group of elements.
- Errors
- No measurement is exact, they all contain some degree of errors.
- Es
- Einsteinium artificial radioactive element found in the debris of an H bomb.
- Essential Oil
- Any oil that smells the same as the vegetable from which it was obtained and has a low boiling point.
- Ester
- Compound formed by the reaction between an alcohol and an acid, with the elimination of water.
- Ethanal
- Also known as acetaldehyde, it is a colourless fruity smelling liquid that with further oxidation forms acetic acid.
- Ethanamide
- Also known as Acetamide.
- Ethane
C2H6 Second member of the alkane series, a colourless, odourless gas. - Ethanenitrile
- Also known as Acetonitrile.
- Ethanoic Acid
- Alternative name for Acetic Acid.
- Ethanol
C2H5OH Prepared by the fermentation of sugar. - Ethanol E10
- Ethanol mixture that contains 10% ethanol, 90% unleaded gasoline.
- Ethanol E85
- Refers to a fuel blend of 85 percent ethanol and 15 percent gasoline.
- Ethanoyl Chloride
- Also known as Acetyl Chloride.
- Ethene
- Alternative name for Chloroform.
- Ethyl
- The monovalent radical -C2H5
- Ethyl Acetate
CH3COOCH2CH3 A flammable liquid with a fruity odour, used in flavourings and as a solvent. - Ethyl Bromide
- Alternative name for Bromoethane.
- Ethyl Chloride
- Alternative name for Chloroethane.
- Ethylamine
CH3CH2NH2 Widely used in chemical industry and organic synthesis, it has a strong ammonia-like odor. - Ethylene
- Also known as Ethene this is a colourless inflammable gas with a sweet smell used as an anaesthetic and in the manufacture of polythene.
- Ethylene Aldehyde
- Alternative name for Acrolein.
- Ethylenecarboxylic Acid
- Alternative name for Acrylic Acid.
- Ethyne
- Also known as Acetylene, used for welding as the flame temperature is roughly 3300°C when burnt with oxygen.
- Eu
- A europium is a ductile silvery metal which reacts rapidly with air and water.
- Europium
- A ductile silvery metal which reacts rapidly with air and water.
- Eutectic Alloy
- An alloy that changes directly from a solid to a liquid with no plastic or semiliquid state.
- Eutectic Mixture
- A mixture of two or more substances with melting point lower than that for any other mixture of the same substances.
- Excitotoxin
- An excitotoxin is a toxic molecule that stimulates nerve cells so much that they are damaged or killed.
- Exergonic
- Refers to a reaction for which the free energy of the system decreases.
- Exothermic
- Reaction that gives off heat to the environment.
- Experimental Yield
- The measured amount of product produced in a chemical reaction.
- Extensive Properties
- Properties which are dependent on the amount of the substance.
- Extrinsic Semiconductor
- A semi-conducting material for hich the electrical behavior is determined by impurities.
- F
- Fluorine is a pale greenish yellow gas that is the first in the halogen group.
- Face Centred Cubic
- Roughly 20% of the elements crystallize with face centred cubic structures.
- Fatigue
- An important mode of failure of engineering components subjected to dynamic stresses.
- Fe
- Iron is one of the most abundant metallic elements (41000 ppm) and probably one of the most important, being used on the largest scale of any metal.
- Fe2O3
- Chemical formula for Iron III Oxide.
- FeCl2
- Chemical formula for Iron II Chloride.
- FeCl3
- Chemical formula for Iron III Chloride.
- FeO
- Chemical formula for Iron II Oxide.
- Fermium
- A man-made element with an atomic number of 100.
- Ferric Oxide
- Old name for Iron III Oxide.
- Ferroelectric
- A dielectric material that may exhibit polarization in the absence of an electric field.
- Ferromagnetism
- Permanent and large magnetizations found in some metals (e.g., Fe, Ni, and Co), which result from the parallel alignments of neighboring magnetic moments.
- Ferrous Chloride
- Old name for Iron II Chloride.
- Ferrous Oxide
- Old name for Iron II Oxide.
- Ferrous Sulphide
- Old name for Iron Sulphide.
- Ferrum
- Latin for iron, hence the symbol Fe.
- FeS
- Chemical formula for Iron Sulphide.
- FeS2
- Chemical formula for Iron II Sulphide.
- FeSO4
- Chemical formula for Iron II Sulphate.
- Fibre
- Any material that has been drawn into a cylinder with a length-to-diameter ratio greater than about ten.
- Fields Metal
- A low melting point alloy. 51% Indium, 32.5% Bismuth, and 16.5% Tin.
A non-toxic replacement for Wood's Metal. - Filler
- An inert foreign substance added to a matrix to improve or modify its properties.
- Fire Air
- An old name given to pure oxygen.
- Fire Damp
- The gases found naturally in coal are a mixture of methane and other hydrocarbons. Given the name as they are highly combustible when mixed with air.
- First Order Reaction
- The sum of concentration exponents in the rate law for a first order reaction is one. Many radioactive decays are first order reactions.
- Flame Test
- A test to identify some metals, e.g. with sodium the flame turns orange.
- Flammable
- Substance that can easily be set on fire and that will burn readily or quickly.
- Flash Point
- The temperature when vapour pressure of a substance becomes high enough to allow the air/vapour layer over the substance to be ignited.
- Flint Glass
- An optical glass with higher dispersion and higher refractive index than crown glass; a heavy, brilliant glass, softer than crown glass.
- Fluorescence
- The property of a material whereby it emits visible light when it is illuminated by ultraviolet light.
- Fluorine
- A pale greenish yellow gas that is the first in the halogen group.
- Fluorotrichloromethane
- Alternative name for Trichlorofluoromethane.
- Fm
- Fermium is a man-made element with an atomic number of 100.
- Foam
- A colloid in which bubbles of gas are suspended in a solid or liquid.
- Fools Gold
- Name given to Iron II Sulphide due to its colour and texture.
- Formaldehyde
H2CO Used widely by industry to manufacture building materials and numerous household products. It is also a by-product of the incomplete combustion of carbo containing materials. - Formic Acid
- Another name for Methanoic Acid.
- Formic Anammonide
- Alternative name for Hydrogen Cyanide.
- Formonitrile
- Alternative name for Hydrogen Cyanide.
- Formyl Trichloride
- Alternative name for Chloroform.
- Formylic Acid
- Another name for Methanoic Acid.
- Fossil Fuel
- A fuel such as coal, oil or natural gas that was formed through the decomposition of ancient plant and animal life.
- Fr
- Francium is the heaviest alkali metal with no stable isotopes.
- Francium
- The heaviest alkali metal with no stable isotopes.
- Freeze
- To change from a liquid to a solid by cooling.
- Frenkel Defect
- In an ionic solid, a cation-vacancy and cation-interstitial pair.
- Freon-10
- Alternative name for Carbon Tetrachloride.
- Freon-11
- Alternative name for Trichlorofluoromethane.
- Freon-14
- Alternative name for Tetrafluoromethane.
- Fuel
- Any substance burned for heat or power.
- Fuel Cell
- A device that converts the chemical energy obtained from a redox reaction directly into electrical energy.
- Fullerene
- A form of carbon consisting of 60 carbon atoms bound together to make a roughly spherical buckyball.
- Fulmination
- Any very rapid reaction which produces heat, light, and noise - explosions.
- Furanose Ring
- A five-membered cyclic hemiacetal or hemiketal of a carbohydrate.
- Fused Quartz
- The glassy isotropic form of quartz.
- Fused Silica
SiO2 The glassy isotropic form of quartz. - Ga
- Gallium is one of four metals which can be liquid at room temperature
- GAA
- Abbreviation of Glacial Acetic Acid.
- Gadolinium
- A silvery white metal which is ductile and malleable. It is stable in a dry atmosphere but forms an oxide coating when exposed to moist air.
- Galena
- A Lead Sulphide and the most common ore of lead.
- Gallium
- One of four metals which can be liquid at room temperature.
- Galvanic Cell
- A cell in which chemical change is the source of electrical energy.
- Galvanic Corrosion
- Corrosion associated with the current of a galvanic cell consisting of two dissimilar conductors in an electrolyte or two similar conductors in dissimilar electrolytes.
- Galvanic Couple
- A pair of dissimilar conductors, commonly metals, in electrical contact.
- Galvanic Current
- The electric current that flows between metals or conductive nonmetals in a galvanic couple.
- Gamma Iron
- The face-centered cubic form of pure iron, stable from 910 to 1400°C.
- Gas
- Matter with no definite shape or volume.
- Gas Constant
- Molar Gas Constant, R = 8.31441 JK-1mol-1
- Gasification
- A process for converting materials such as coal, petroleum, or biomass, into carbon monoxide and hydrogen by reacting the raw material at high temperatures with a controlled amount of oxygen.
- Gay-Lussac, Joseph Louis
- Developed the law of volumes concerning the combination of gases and discovered boron.
- Gd
- Gadolinium is a silvery white metal which is ductile and malleable. It is stable in a dry atmosphere but forms an oxide coating when exposed to moist air.
- Ge
- Germanium is a silvery white brittle metalloid member of the carbon group of elements. Its physical properties being similar to those of silicon.
- Geometric Isomer
- Molecules that have the same molecular formula and bond connections, but distinctly different shapes.
- German Silver
- This describes a number of alloys that contain copper (25 to 50%), zinc (10 to 35%) and nickel (5 to 35%) within the limits given.
- Germanium
- A silvery white brittle metalloid member of the carbon group of elements. Its physical properties being similar to those of silicon.
- Gibbs Free Energy
- A function of the system related to Suniv. It is used to determine the spontaneity of a reaction.
- Gibbsite
- White crystalline mineral consisting of aluminum hydroxide; a constituent of bauxite and a source of alumina.
- Glass
- Transparent or translucent substance that is physically neither a solid or liquid. It is made by fusing certain types of sand (silica).
- Glass Ceramic
- A fine-grained crystalline material that was formed as a glass and subsequently devitrified (crystallized).
- Glass Transition Temperature
- The temperature at which, upon cooling, a noncrystalline ceramic or polymer transforms from a supercooled liquid into a rigid glass.
- Glucose
- A sugar. It is made by plants during photosynthesis.
- Glue
- Cement or adhesive that is used to fix two or more parts together.
- Glycerol
- Thick sweet liquid used in the manufacture of explosives.
- Glycine
NH2CH2COOH A naturally occurring aliphatic amino acid, found in large quantities in gelatin. - Gold
- A soft metal with a characteristic yellow colour. It is the most malleable and ductile of any element. It is unaffected by air, water, alkalis and acids.
- Graphite
- An amorphous form of carbon, made of carbon atoms bound hexagonally in sheets.
- Green Vitriol
- Hydrated Iron II Sulphate.
- Greenockite
- Mineral, main source of cadmium sulphide.
- Group
- A vertical column in the periodic table.
- Guaranine
- An alkaloid extracted from guarana, the same as Caffeine.
- Gunmetal
- This is a copper-tin alloy, similar to bronze, used where resistance to corrosion and/or wear required. Composition: 88% copper, 8% tin, 4% zinc.
- Gunpowder
- Any of several low-explosive mixtures.
- Gy
- An abbreviation of gray, the amount of energy actually absorbed in some material, and is used for any type of radiation and any material.
- Gypsum
- The old name for Calcium Sulphate.
- H
- Hydrogen is the least dense element. It has metallic and non-metallic properties.
- H2C2O4
- Chemical formula for Oxalic Acid.
- H2CO
- Chemical formula for Formaldehyde.
- H2CO3
- Chemical formula for Carbonic Acid.
- H2O
- Chemical formula for water
- H2O2
- Hydrogen peroxide.
- H2S
- Hydrogen sulphide.
- H2Se
- Chemical formula for Hydrogen I Selenide.
- H2SO3
- Chemical formula for Sulphurous Acid.
- H2SO4
- Chemical formula for Sulphuric Acid.
- H2Te
- Chemical formula for Hydrogen I Telluride.
- H3PO4
- Chemical formula for Phosphoric Acid.
- ha
- An abbreviation of hectare, a derived SI unit of area that is mainly used in agriculture to describe the area of fields.
- Haber Process
- An industrial process in which ammonia is manufactured by direct combination of its elements.
- Hafnium
- A silvery coloured, ductile metal which is found in all minerals containing zirconium.
- Halide
- A compound composed of two elements, one of which is a halogen (flourine, chlorine, bromine, iodine and astatine).
- Halogen
- Group of elements with similar bonding properties, consisting of flourine, chlorine, bromine, iodine and astatine.
- Halon
- Organic chemical compounds containing one or two carbon atoms, together with bromine and other halogens.
- Hazard
- The potential that the use of a product will result in an adverse effect on a person or the environment.
- HCL
- Hydrochloric acid.
- HCL
- Hydrogen chloride.
- HCN
- Chemical formula for Hydrogen Cyanide.
- HCP
- Abbreviation of Hexagonal Close Packed, a crystal structure found for some metals.
- He
- Helium is an inert gaseous element.
- Heat of Combustion
- The amount of energy released in burning completely an amount of substance.
- Heat of Hydration
- The enthalpy change associated with placing gaseous molecules or ions in water.
- Heat of Neutralization
- The heat released by an acid-base neutralization reaction running at constant pressure.
- Heat of Reaction
- The heat absorbed or released by a chemical reaction running at constant pressure.
- Heat of Solution
- The enthalpy change associated with dissolving a solute in a solvent.
- Heat of Sublimation
- The change in enthalpy when one mole of solid vaporizes to form one mole of gas.
- Heat of Vaporization
- The energy required to vaporize one mole of a liquid at a pressure of one atmosphere.
- Heavy Metals
- Metallic elements with high atomic weights can damage living things at low concentrations and tend to accumulate in the food chain.
- Heavy Water
D2O Water that contains 2H, rather than 1H. Heavy water is about 11% denser than ordinary water. - Helium
- An inert gaseous element.
- Helmholtz Free Energy
- Energy released or absorbed in a reaction occurring reversibly at constant volume and temperature.
- Hendecane
- Another name for Undecane.
- Hepatic Air
- Old name for hydrogen sulphide.
- Heptane
C7H16 An alkane hydrocarbon. A constituent of petroleum. - Hermetic
- Sealing of an object so it is airtight.
- Hess′s Law
- In going from a particular set of reactants to a particular set of products, the enthalpy change is the same whether the reaction takes place in one step or a series of steps; in other words, enthalpy is a state function.
- Heterocyclic Compounds
- In chemistry, heterocyclic compounds are cyclic compounds in which the ring system of the molecule contains other elements than carbon.
- Heterogeneous Catalysis
- A form of catalysis in which the catalyst is in a different physical state than the reactants.
- Hexagonal Close Packed
- A crystal structure found for some metals.
- Hexane
C6H14 Hexane isomers are largely unreactive, and are frequently used as an inert solvent in organic reactions because they are very non-polar. - Hf
- Hafnium is a silvery coloured, ductile metal which is found in all minerals containing zirconium.
- HF
- Chemical formula for Hydrofluoric Acid.
- Hg
- The most common liquid metal at room temperature.
- Hg2Cl2
- Chemical formula for Mercury I Chloride.
- HgCl2
- Chemical formula for Mercury II Chloride.
- HgO
- Chemical formula for Mercury II Oxide.
- HgS
- Mercuric Sulphide, the ore of mercury. Occuring as red crystals.
- HI
- Chemical formula for Hydrogen Iodide.
- HNO3
- Chemical formula for Nitric Acid.
- Ho
- Holmium is a member of the lanthanide group with properties closely resembling those of erbium and dysprosium.
- Holmium
- A member of the lanthanide group with properties closely resembling those of erbium and dysprosium.
- Homogeneous Catalysis
- A form of catalysis in which the catalyst is in the same physical state as the reactants.
- Homogeneous Mixture
- A sample of matter consisting of more than one pure substance with properties that do not vary within the sample.
- Homopolymer
- A polymer having a chain structure in which all mer units are of the same type.
- HRb
- Chemical formula for Rubidium Hydride.
- Hunds Rule
- When electrons are put into orbitals having the same energy, degenerate orbitals, one electron is put into each orbital before putting a second electron into an orbital.
- Hydrargyrum
- The old name for Mercury and from where the chemical symbol Hg was derived.
- Hydrate
- A compound that has discrete water molecules combined with it.
- Hydrated Beryllia
- Alternative name for Beryllium Hydroxide.
- Hydration
- The combination of water and another substance to produce a single product.
- Hydraulic Set Cement
- A cement that sets through reaction with water.
- Hydride
- A compound containing a negatively charged hydrogen.
- Hydrocarbon
- A chemical containing only hydrogen and carbon.
- Hydrochloric Acid
HCl A solution of hydrogen chloride in water. Concentrated acid is a colourless, fuming, corrosive liquid. - Hydrochloride
- Alternative name for Hydrogen Chloride.
- Hydrocyanic Acid
- A solution of Hydrogen Cyanide in water.
- Hydrofluoric Acid
HF Aqueous solution of hydrogen fluoride. Dissolves most metals and etches glass. - Hydrogen
- The least dense element. It has metallic and non-metallic properties.
- Hydrogen Arsenide
AsH3 Intensely poisonous colourless gas. Also known as Arsine. - Hydrogen Bonding
- Strong type of intermolecular dipole-dipole attraction. Occurs between hydrogen and fluorine, oxygen or nitrogen.
- Hydrogen Carboxylic Acid
- Another name for Methanoic Acid.
- Hydrogen Chloride
- Dissolves in water to produce hydrochloric acid.
- Hydrogen Cyanide
HCN Colorless, very poisonous and highly volatile liquid. - Hydrogen I Nitride
- Modern name for Ammonia.
- Hydrogen I Selenide
H2Se Colourless gas. - Hydrogen I Telluride
H2Te Colourless gas. - Hydrogen Iodide
HI Colourless gas. - Hydrogen Peroxide
H2O2 A colourless, viscous, unstable liquid compound of hydrogen and water with oxidising and reducing properties. Used for bleaching wool, silk, linens, furs and hair products since the 19th century. During the Second World War hydrogen peroxide was used as a propellant in V1 rockets and was subsequently also used as a propellant for submarines. Hydrogen peroxide is also used as a preservative and disinfectant and is used by archaeologists to dissolve clay from finds. - Hydrogen Persulphide
H2S2 Colourless liquid. - Hydrogen Sulphide
- Poisonous and smells of rotten eggs.
- Hydrogenation
- A chemical reaction in which hydrogen is added to a compound.
- Hydroiodic Acid
- Alternative name for Hydrogen Iodide.
- Hydrolysis
- When water reacts with another substance and as a result the oxygen in water makes a bond with the substance.
- Hydrophilic
- A polar molecule or group that can form strong hydrogen bonds with water.
- Hydrophobic
- A nonpolar molecule or group that has little affinity for water.
- Hydroquinone
- A reducing agent used in photographic developers.
- Hydroxy Group
- An -OH group attached to an organic molecule.
- Hydroxybutanedioic Acid
C4H6O5 An organic dicarboxylic acid extracted from apples and various other fruits. - Hygroscopic
- Able to absorb moisture from air.
- I
- Iodine is in the halogen group of elements.
- Ice
- Formed when water is cooled below its freezing point.
- Immiscible
- Incapable of being mixed.
- In
- Indium is a soft, malleable and ductile metal which is generally unaffected by air or water but is soluble in acids.
- Inclusion
- Foreign particle present as an undesirable impurity in a material.
- Inconel
- A nickel based alloy with good corrosion resistance.
- Indicator
- A substance that undergoes a sharp, easily observable change when conditions in its solutions change.
- Indicator Diagram
- A plot of pressure vs. volume.
- Indirect Titration
- Determining the concentration of an analyte by reacting it with a known number of moles of excess reagent.
- Indium
- A soft, malleable and ductile metal which is generally unaffected by air or water but is soluble in acids.
- Inert Gas
- A gas which does not normally combine chemically with other elements.
- Inflammable Air
- An old name for Hydrogen.
- Initiator
- A compound required to start a chain reaction.
- Intensive Properties
- Properties which are independent of the amount of the substance.
- Intermediate Species
- Species formed in a reaction consisting of more than one step.
- Intermetallic
- A compound of two metals that has a distinct chemical formula. The bonds in intermetallic compounds are often partly ionic.
- Intermolecular Forces
- Forces between molecules.
- Internal Energy
- A property of a system that can be changed by a flow of work, heat or both.
- Interstitial Site
- Octahedral and tetrahedral open spaces within a close-packed arrangement of atoms or ions in which a cation can fit.
- Intramolecular Forces
- Forces within molecules. Forces caused by the attraction and repulsion of charged particles.
- Invar
- An alloy of iron and nickel.
- Iodine
- In the halogen group of elements.
- Iodine Number
- The number of grams of iodine required to saturate 100 grams of fat.
- Ion
- An atom, or group of atoms, which has either gained or lost electrons.
- Ion Dipole Forces
- Intermolecular force that exist between charged particles and partially charged molecules.
- Ionic Bond
- This describes the electrostatic attraction of two oppositely charged ions in a crystalline lattice.
- Ionization Energy
- Energy required to remove an electron from a specific atom.
- Ionizing Radiation
- A particle or a photon with enough energy to knock off an electron from an atom.
- Ir
- Iridium is a rare, precious metallic element which is hard, brittle and has a low ductility.
- Iridium
- A rare, precious metallic element which is hard, brittle and has a low ductility.
- Iridosmine
- Iridosmine (osmiridium) is a naturally occurring alloy of osmium and iridium.
- Iron
- One of the most abundant metallic elements (41000 ppm) and probably one of the most important, being used on the largest scale of any metal.
- Iron Hydroxide
FeO(OH) Found as the minerals Siderogel and Feroxyhyte. It also has a variant known as Lepidocrocite. - Iron II Chloride
FeCl2 Pale yellow to white crystalline solid. - Iron II Hydroxide
Fe(OH)2 Green colour. - Iron II Oxide
FeO Black colour powder. The powder in particular can cause explosions as it readily ignites. - Iron II Sulphate
FeSO4 Also known as the mineral Melanterite or Copperas. Green Vitriol is hydrated Iron II Sulphate. - Iron II Sulphide
FeS2 A brassy yellow colour. Also known as pyrite, iron pyrites and fools gold. - Iron III Chloride
FeCl3 Brown black or green crystalline solid. - Iron III Oxide
Fe2O3 Known in its natural state as Haematite, but also purified for use as a coating in magnetic audio and computer media, where it is known as Ferric oxide. - Iron Pyrites
- Old name for Iron II Sulphide.
- Iron Sulphide
FeS White crystalline solid. - Isomer
- Molecules with identical molecular formulas but different structural formulas.
- Isomerization
- A chemical change that involves a rearrangement of atoms and bonds within a molecule, without changing the molecular formula.
- Isosteric
- Having identical valence electron configurations.
- Isotactic
- A type of polymer chain configuration wherein all side groups are positioned on the same side of the chain molecule.
- Isotone
- One of a group of atoms or ions with nuclei that contain the same number of neutrons but different numbers of protons.
- Isotonic
- Refers to solutions that have equal osmotic pressure.
- Isotopes
- Two atoms having the same number of protons but different numbers of neutrons are said to be isotopes of each other.
- Isotopic Abundance
- The fraction of atoms of a given isotope in a sample of an element.
- Isotopic Mass
- The mass of a single atom of a given isotope, usually given in daltons.
- Isotropic
- Having identical values of a property in all crystallographic directions
- K
- Potassium is a soft, silvery coloured metal, which like other members of the alkali group of metals, is extremely reactive.
- K2O
- Chemical formula for Potassium Oxide.
- K2O2
- Chemical formula for Potassium Peroxide.
- K2S
- Chemical formula for Potassium Sulphide.
- Kalium
- The old name for Potassium and from where the chemical symbol K was derived.
- Kapok
- Used as an insulating or flotation material it comes from the seed hairs of the kapok tree (Ceiba Pentranda).
- KBr
- Chemical formula for Potassium Bromide.
- KCl
- Chemical formula for Potassium Chloride.
- Keir Metal
- Brass containing 55% copper, 40% zinc and 5% iron. Patented in 1779 by James Keir (Chemist, Geologist, Industrialist and Inventor) and used for the manufacture of window frames.
- Ketone
- Compunds containing a carbonyl group (-CO-) attached to two hydrocarbon radicals. The simplest ketone is acetone (CH3COCH3).
- KF
- Chemical formula for Potassium Fluoride.
- KI
- Chemical formula for Potassium Iodide.
- Kiln
- A furnace in which ceramics are fired.
- Kinetics
- The study of how fast reactions occur.
- kJ
- An abbreviation of kilojoule, one thousand joules. The SI unit of energy is the joule.
- KMnO4
- Potassium Manganate VII
- KNO3
- Chemical formula for Potassium Nitrate.
- KO2
- Chemical formula for Potassium Superoxide.
- KOH
- Potassium Hydroxide.
- Kr
- Krypton is a rare gaseous element.
- Krypton
- A rare gaseous element.
- La
- Lanthanum is a soft, ductile, white metallic element which oxidises rapidly in air.
- Lacquer
- A fast-drying usually clear coating that is highly flammable and dries by solvent evaporation only.
- Lanthanum
- A soft, ductile, white metallic element which oxidises rapidly in air.
- Lard Oil
- An oil made from animal fats usually mixed with mineral oils to reduce its cost and improve its qualities. Used in engineering as a cutting oil.
- Lattice
- An orderly arrangement of atoms in a material.
- Lattice Parameter
- The combination of unit cell edge lengths and interaxial angles that defines the unit cell geometry.
- Laughing Gas
- Nitrous oxide, an anaesthetic.
- Lawrencium
- The only known isotope has a half life of 8 seconds.
- Lead
- A soft, malleable and ductile metallic element that has been known of and used since prehistoric times.
- Lead II Carbonate
PbCO3 Decomposes readily into Lead II Oxide and carbon dioxide at 200°C and can be reduced to lead using carbon monoxide. - Lead II Chromate IV
PbCrO4 Used as a pigment due to the strong yellow colour. - Lead II Oxide
PbO Lead monoxide varies in colour from pale yellow to brown, used in the manufacture of glass, paints, varnishes and glazes. - Lead II Sulphide
PbS Grey crystalline solid. - Lead IV Oxide
PbO2 Lead dioxide a dark brown powder, strong oxidizing agent. - Lean Burn
- A fuel air mixture that contains higher amounts of air than normally used.
- Leclanché Cell
- A electrolytic cell also known as a dry cell that uses a moist paste rather than a liquid as an electrolyte.
- Lepidocrocite
- Alternative name for Iron Hydroxide.
- Lever Rule
- Mathematical expression whereby the relative phase amounts in a two-phase alloy at equilibrium may be computed.
- Levorotatory
- A chiral molecule which rotates plane-polarized light to the left.
- Li
- Lithium is a soft, silver metal, and is the first member of the alkali group of metals.
- Li2
- Chemical formula for Lithium I Oxide.
- Li2O2
- Chemical formula for Lithium I Peroxide.
- Li3N
- Chemical formula for Lithium I Nitride.
- LiBr
- Chemical formula for Lithium I Bromide.
- LiCl
- Chemical formula for Lithium I Chloride.
- LiF
- Chemical formula for Lithium I Fluoride.
- Ligand
- A molecule or ion that binds to a metal cation to form a complex.
- Lignite
- A type of coal with lowest carbon content (25% to 35%) and a low heat value called "brown coal", used mainly for electric power generation.
- LiH
- Chemical formula for Lithium I Hydride.
- LiI
- Chemical formula for Lithium I Iodide.
- Limestone
- Naturally occuring Calcium Carbonate.
- Limiting Reagent
- The reactant that will be exhausted first.
- Linseed Oil
- Obtained from the seeds flax. Originally used in the production of paints.
- LiO2
- Chemical formula for Lithium Superoxide.
- Lipid
- A diverse group of organic molecules that contain long hydrocarbon chains or rings and are hydrophobic.
- Lipowitz Alloy
- A low melting point alloy used to form shields in radiotherapy.
- Liquefied Natural Gas
- Natural gas that has been refrigerated to cryonic temperatures where the gas condenses into a liquid.
- Liquid
- Matter with a definite volume that takes the shape of its container.
- Litharge
- Lead monoxide varies in colour from pale yellow to brown, used in the manufacture of glass, paints, varnishes and glazes.
- Lithium
- A soft, silver metal, and is the first member of the alkali group of metals.
- Lithium I Bromide
LiBr White crystalline solid. - Lithium I Chloride
LiCl White crystalline solid. - Lithium I Fluoride
LiF White crystalline solid. - Lithium I Hydride
LiH White to grey crystalline solid. - Lithium I Iodide
LiI White crystalline solid. - Lithium I Nitride
Li3N Purple or red crystalline solid. - Lithium I Oxide
Li2O White crystalline solid. - Lithium I Peroxide
Li2O2 White crystalline solid. - Lithium Superoxide
LiO2 Yellow crystalline solid. - Litmus
- A mixture of pigments extracted from certain lichens that turns blue in basic solution and red in acidic solution.
- Litmus Paper
- Paper impregnated with litmus, usually cut in narrow strips.
- LNG
- Abbreviation of Liquefied Natural Gas.
- Lock and Key Model
- A model that explains the role of enzymes in chemical reactions by assuming that the reactants fit into the enzyme like a key fits into a lock.
- London Force
- An intermolecular attractive force that arises from a cooperative oscillation of electron clouds on a collection of molecules at close range.
- Lone Pair
- Electrons that are not involved in bonding.
- lox
- Liquid oxygen.
- Lr
- The only known isotope of lawrencium has a half life of 8 seconds.
- Lu
- Lutetium is the hardest, densest and one of the rarest of the lanthanide group of elements.
- Lucite
- Tradename for Polymethyl Methacrylate Resin.
- Lunar Crystals
- Old name for Silver Nitrate.
- Lutetium
- The hardest, densest and one of the rarest of the lanthanide group of elements.
- Lye
- Alternative name for Sodium Hydroxide.
- Macromolecule
- A huge molecule made up of thousands of atoms
- Macroscopic
- Anything big enough to be seen with the naked eye.
- Madelung Constant
- A constant representing the sum of the mutual potential coulombic attractive energy of all the ions in a lattice in the equation for the energy of an ionic crystal.
- Magnalium
- An alloy of magnesium and aluminium used in aircraft manufacture.
- Magnesium
- A brilliant white metal, which is relatively soft and is one of the more abundant elements in the earth’s crust.
- Magnesium Fluoride
- Used as antireflection coating for lenses because of its low refractive index.
- Magnesium Oxide
- Formed by igniting Magnesium in air.
- Malic Acid
- Another name for Hydroxybutanedioic Acid.
- Manganese
- A hard, brittle, silvery coloured, metallic element which resembles iron in being moderately reactive and dissolving in cold, dilute non-oxidising acids.
- Manganese Bronze
- A copper alloy containing zinc, manganese and a small quantity of nickel.
- Manganese IV Oxide
MnO2 This blackish or brown solid occurs naturally as the mineral pyrolusite. - Manganin
- Alloy with 84% copper, 12% manganese and 4% nickel used in wire form for making heating elements.
- Marble
- A granular metamorphosed limestone that is often polished and used for decoration.
- Marsh Gas
- The natural occurence of methane.
- Martensite
- Martensite is a microconstituent or structure in quenched steel characterized by an acicular or needle-lie pattern on the surface of polish.
- Mass Action Law
- The law which describes the relation between the densities of species involved in a chemical reaction.
- Mass Spectrometer
- An instrument for producing ions in a gas and determining their mass and hence composition.
- Mass Spectrum
- A plot showing the results of a mass spectrometry experiment, which shows the presence of particles with different masses as a series of sharp, separate peaks.
- Massicot
- Mineral form of Lead II Oxide.
- Material Safety Data Sheet
- Safety information sheet for a particular substance that lists physical properties, hazards, cleanup and disposal procedures, fire and explosion data, and protective equipment required.
- Md
- Mendelevium is a man-made element with an atomic number of 101.
- Measurement
- The collection of quantitative data.
- Melanterite
- The mineral name for Iron II Sulphate.
- Melting Point
- The temperature at which a solid substance changes to a liquid state.
- Mendelevium
- Man-made element with an atomic number of 101.
- Mer
- The group of atoms that constitutes a polymer chain repeat unit.
- Mercuric Chloride
- Another name for Mercury II Chloride.
- Mercuric Oxide
- Another name for Mercury II Oxide.
- Mercuric Sulphide
HgS The ore of mercury. Occuring as red crystals. - Mercurous Chloride
- Another name for Mercury I Chloride.
- Mercury Dichlorate
- Another name for Mercury II Chloride.
- Mercury Hg
- The most common liquid metal at room temperature.
- Mercury I Chloride
Hg2Cl2 Dense white or yellowish-white odorless solid. It was used in medicine as a diuretic and laxative although this is now discontinued. - Mercury II Chloride
HgCl2 One of the most toxic forms of Mercury. - Mercury II Oxide
HgO A red or orange solid at room temperature that is used in the production of Mercury as it decomposes readily. - Metabolite
- A compound produced by metabolic reactions.
- Metal
- A metal is a substance that conducts heat and electricity, is shiny and reflects many colors of light, and can be hammered into sheets or drawn into wire.
- Metallic Compound
- Compound that contains at least one metallic element.
- Metallic Radius
- The atomic radius from as established by measuring the distances between atoms in metallic crystals.
- Metallurgy
- The science and technology of metals and alloys.
- Methanal
- Alternative name for Formaldehyde.
- Methane
- The first alkane. Occurs naturally as marsh gas and in oil wells.
- Methane Trichloride
- Alternative name for Chloroform.
- Methanoic Acid
CH2O2 Most famous for it's occurrence in Ant and Bee venom. - Methanol
- A colourless liquid also known as methyl alcohol.
- Methenyl Trichloride
- Alternative name for Chloroform.
- Methyl
- The monovalent radical -CH3
- Methyl Acetate
C3H6O2 A clear, flammable liquid with a characteristic, not unpleasant smell like certain glues or nail polish removers. - Methyl Alcohol
- Also known as methanol.
- Methyl Bromide
- Alternative name for Bromomethane.
- Methyl Chloride
- Alternative name for Chloromethane.
- Methyl Cyanide
- Also known as Acetonitrile.
- Methyl Ethanoate
- Alternative name for Methyl Acetate.
- Methyl Phenyl Ether
- Also known as Anisole.
- Methyl Trichloride
- Alternative name for Chloroform.
- Methylbenzene
- Also known as toluene.
- Methylene Chloride
- Alternative name for Dichloromethane.
- Methylene Dichloride
- Alternative name for Dichloromethane.
- Mg
- A brilliant white metal, which is relatively soft and is one of the more abundant elements in the earth’s crust.
- Mica
- A group of silicates with similar chemical composition. Used as an electrical insulator.
- Microscopic
- Refers to objects that are too small for the unaided eye to see.
- Microstructure
- The structural features of an alloy that are subject to observation under a microscope.
- Mild Steel
- A term used for low-carbon machine steel.
- Milk
- Opaque white liquid secreted by female mammals for feeding young.
- Miller Indices
- A set of three integers that designate crystallographic planes, as determined from reciprocals of fractional axial intercepts.
- Miller-Bravis Indices
- A set of four integers that designate crystallographic planes in hexagonal crystals.
- Mineral Wool
- Also known as rock wool.
- Mischmetal
- An alloy of cerium, rare-earth metals and iron.
- Miscible
- Two liquids are considered "miscible" or mixable if shaking them together results in a single liquid phase, with no meniscus visible between layers of liquid.
- Mixed Dislocation
- A dislocation that has both edge and screw components.
- Mixture
- Two or more substances which are not chemically bonded together.
- Mn
- Manganese is a hard, brittle, silvery coloured, metallic element which resembles iron in being moderately reactive and dissolving in cold, dilute non-oxidising acids.
- Mo
- Molybdenum is a lustrous, silvery coloured metal that resembles tungsten with which it tends to be paired in the transition series in the periodic table.
- mol
- Abbreviation of Mole, the SI unit of Amount of Substance.
- Molality
- Concentration measured as moles of solute per kilogram of solvent.
- Molar Gas Constant
- R = 8.31441 JK-1mol-1
- Molar Heat Capacity
- The amount of heat required to raise the temperature of 1mol of a substance through 1K.
- Molar Heat of Combustion
- The amount of energy released in burning completely one mole of substance.
- Molar Volume
- The volume occupied by one mole of a substance under specified conditions.
- Molarity
- Concentration of a solution measured as the number of moles of solute per litre of solution.
- Mole
- The SI unit of the Amount of Substance. It is the amount of substance of a system which contains as many elementary entities as there are atoms in 0.012 kilogram of carbon 12.
- Mole Fraction
- The number of moles of a particular substance expressed as a fraction of the total number of moles.
- Molecular Equation
- A molecular equation is a balanced chemical equation in which ionic compounds are written as neutral formulas rather than as ions.
- Molecular Formula
- Shows the number of atoms of each element present in a molecule.
- Molecular Geometry
- Shape of a molecule, based on the relative positions of the atoms.
- Molecular Sieve
- A material that contains many small cavities interconnected with pores of precisely uniform size.
- Molecular Weight
- The combined weight (as given on the periodic table) of all the elements in a compound.
- Molecule
- The smallest part of an element or of a covalently bonded compound that can exist independently and still retain the ordinary chemical properties of that element or compound.
- Molybdenum
- A lustrous, silvery coloured metal that resembles tungsten with which it tends to be paired in the transition series in the periodic table.
- Monatomic Ion
- An ion formed from a single atom by the loss or gain of electrons.
- Monobromomethane
- Alternative name for Bromomethane.
- Monochloroethane
- Alternative name for Chloroethane.
- Monomer
- A molecule that, under the correct conditions, can link together with others to form larger molecules called polymers.
- Montroydite
- Another name for Mercury II Oxide.
- Mossbauer Spectrometer
- An instrument that provides information on the bonding of an atom in a mineral by bombarding it with gamma rays.
- Mumetal
- An alloy of high magnetic permeability containing up to 78% nickel with iron, copper and manganese.
- Muntz Metal
- Stonger than normal brass and used for castings and hot worked items. 60 % Copper 40 % Zinc
- Mustard Gas
- Common name for Dichlorodiethyl Sulphide a gas used in warfare.
- N
- A gaseous colourless and odourless element that makes up about 80% of the atmosphere.
- N2O
- Chemical formula for Nitrous Oxide.
- Na
- Sodium is a soft, silvery coloured metal which, like other members of the alkali group of metals, is extremely reactive.
- Na2O
- Chemical formula for Sodium Oxide.
- Na2O2
- Chemical formula for Sodium Peroxide.
- NaBr
- Chemical formula for Sodium I Bromide.
- NaF
- Chemical formula for Sodium I Fluoride.
- NaH
- Chemical formula for Sodium Hydride.
- NaI
- Chemical formula for Sodium I Iodide.
- NaNO3
- Chemical formula for Sodium Nitrate.
- Nanometre
- Abbreviated as nm, unit of length equal to 10-9 metres, and equal to 10 Å (Angstroms).
- NaO2
- Chemical formula for Sodium I Oxide.
- NaOCl
- Chemical formula for Sodium Hypochlorite.
- NaOH
- Chemical formula for Sodium Hydroxide.
- Naphtha
- Volatile solvent distilled from petroleum.
- Naphthyleneethylene
- Another name for Acenaphthene.
- Natrium
- Latin for sodium, hence the symbol Na.
- Natural Gas
- The cleanest fossil fuel, and hence a potential short-term aid to slowing climate change.
- Nb
- Niobium is a metallic element that is very reactive and forms an extremely stable oxide when exposed to air which enhances its corrosion resistance.
- Nd
- Neodymium is one of the more reactive members of the lanthanide group.
- Ne
- Neon is a light gaseous inert element.
- Neodymium
- One of the more reactive members of the lanthanide group.
- Neon
- Light gaseous inert element.
- Neptunium
- Produced artificially by nuclear reaction between uranium and neutrons.
- Network Polymer
- A polymer composed of trifunctional mer units that form three-dimensional molecules.
- Neutral Ammonium Fluoride
- Alternative name for Ammonium Fluoride.
- Neutral Solution
- An aqueous solution in which the concentrations of aqueous hydrogen ions and hydroxide ions are equal.
- Newtonian Fluid
- A fluid whose viscosity does not depend on gradients in flow speed.
- Newtons Alloy
- A low melting point alloy.
- NH2CH2COOH
- Chemical formula for Glycine.
- NH2CONH2
- Chemical formula for Carboxamide or more commonly known as Urea.
- NH3
- Chemical formula for Ammonia.
- NH4Cl
- Chemical formula for Ammonium Chloride.
- NH4F
- Chemical formula for Ammonium Fluoride.
- NH4I
- Chemical formula for Ammonium Iodide.
- NH4NH4CO3
- Chemical formula for Ammonium Carbonate.
- NH4NO3
- Chemical formula for Ammonium Nitrate.
- NH4OH
- Chemical formula for Ammonium Hydroxide.
- Ni
- Nickel is a metallic element that is malleable and ductile, and is resistant to corrosion in air or water, and hence is used as a protective coating.
- Niacin
- Vitamin B3 is a crystalline acid found in meat and yeast and produced by the oxidation of nicotine.
- Nichrome
- An alloy of nickel and chromium used for heating elements.
- Nickel
- A metallic element that is malleable and ductile, and is resistant to corrosion in air or water, and hence is used as a protective coating.
- Nickel Brass
- A copper alloy containing zinc and a small quantity of nickel.
- Nicotine
CH14N2 Colourless, very poisonous oily liquid. - Nicotinic Acid
- Vitamin B3 is a crystalline acid found in meat and yeast and produced by the oxidation of nicotine.
- Nimonic
- An alloy consisting of roughly 80% nickel and 20% chromium with additives such as titanium and aluminium.
- Niobium
- As a pure metallic element it is very reactive and forms an extremely stable oxide when exposed to air which enhances its corrosion resistance.
- Nitrate
- The NO3- ion, formed by reaction of nitric acid with a base or a compound containing the NO3- ion.
- Nitre
- Old fashioned name for Potassium Nitrate.
- Nitric Acid
HNO3 Colourless, corrosive, acid liquid that attacks most metals and other substances releasing nitrogen dioxide. - Nitric Oxide
- A colourless gas that forms nitrogen dioxide in contact with air.
- Nitrile
- An organic compound which has a -C=N functional group.
- Nitrite
- The NO2- ion, formed by reaction of nitrous acid with a base or a compound containing the NO2- ion.
- Nitrobenzene
- A yellow liquid obtained from the action of concentrated nitric and sulphuric acid on benzene.
- Nitrogen
- A gaseous colourless and odourless element that makes up about 80% of the atmosphere.
- Nitrogen Oxides
- Several air-polluting gases composed of nitrogen and oxygen which play an important role in the formation of photochemical smog.
- Nitroglycerine
C3H5N3O9 A heavy, yellow or colourless, oily, explosive liquid obtained by nitrating glycerol. - Nitrous Oxide
- Also known as laughing gas, an anaesthetic.
- No
- Nobelium is a man-made element with an atomic number of 102.
- Nobel Prize
- Awarded annually as per Alfred Nobel′s last will and testament.
- Nobelium
- A man-made element with an atomic number of 102.
- Noble Gases
- The gaseous chemical elements helium, neon, argon, krypton, xenon and radon, which are all placed in Group 0 of the Periodic Table.
- Noble Metals
- Metals, such as gold, silver and platinum, that show a marked reluctance to combine with other elements to form compounds.
- Nonane
C9H20 A colourless volatile liquid, an ingredient of ordinary kerosene. - Noncrystalline
- The solid state wherein there is no long-range atomic order. Sometimes used synonymously with the terms amorphous, glassy and vitreous.
- Nonelectrolyte
- A substance which does not ionize in solution.
- Non-Metal
- A term usually reserved for those chemical elements that are very poor electrical conductors in the solid state and liquid states.
- Non-Newtonian Fluid
- A fluid whose viscosity changes when the gradient in flow speed changes.
- Nonpolar Molecule
- A molecule in which the center of positive charge and the center of negative charge coincide.
- Nordic Gold
- A 89% copper, 5% aluminium, 5% zinc and 1% tin alloy.
- NOx
- Abbreviation of Nitrogen Oxides where x represents a varying proportion of oxygen.
- Np
- Neptunium is produced artificially by nuclear reaction between uranium and neutrons.
- Nuclear Binding Energy
- Energy needed to break an atomic nucleus into separate protons and neutrons.
- Nuclear Energy
- Energy stored in the nucleas of an atom.
- Nucleation
- The initial stage in a phase transformation.
- Nucleic Acid
- A polymer made of repeating nucleotides. Examples are DNA and RNA.
- Nylon
- A synthetic polymer used in the manufacture of fibres.
- O
- Oxygen is a colourless and odourless element that is essential for most life forms on earth. It is also the most abundant element on earth.
- O3
- Allotropic form of oxygen containing three atoms in the molecule.
- Octahedral Position
- The void space among closed-packed, hard sphere atoms or ions for which there are six nearest neighbours.
- Octal
- A number system using the base-8, i.e., each digit can be any of 8 values, represented by the digits 0-7.
- Octane
- Flammable liquid compounds found in petroleum and natural gas.
- Octane Number
- A rating of the 'knock' characteristics of motor fuels.
- Octet
- A set of eight valence electrons.
- Octet Rule
- A guideline for building Lewis structures that states that atoms tend to gain, lose, or share valence electrons with other atoms in a molecule until they hold or share eight valence electrons.
- Oil
- An oil is any substance that is in a viscous liquid state at ambient temperatures or slightly warmer, and is both hydrophobic and lipophilic.
- Oil of Bitter Almond
- Old name for Benzaldehyde.
- Oil of Mirbane
- Old name for Nitrobenzene.
- Oil of Vitriol
- Alternative name for Sulphuric Acid.
- Oleoresin
- A natural plant product that contains oil and resins, an example is turpentine.
- Olive Oil
- Obtained from the fruit of Olea Europaea.
- Orbital
- A wavefunction that describes what an electron with a given energy is doing inside an atom or molecule.
- Ore
- A natural mineral mined and treated for extraction of its components.
- Organic Chemistry
- The branch of chemistry that deals with the properties and reactions of carbon-based compounds.
- Organic Compound
- Compounds that contain carbon chemically bound to hydrogen.
- Organochromic Indicators
- Coloured organic compounds that change colour when they chelate different metals.
- Orichalchum
- A Roman brass that consisted of 80% copper and 20% zinc.
- Ormolu
- An alloy of copper, zinc and tin in various proportions with at least 50% copper.
- Orthophospheric Acid
- Another name for Phosphoric Acid.
- Os
- Osmium is a member of the platinum group of metals and is commonly found in conjunction with these elements.
- Osmiridium
- Osmiridium (iridosmine) is a naturally occurring alloy of osmium and iridium. Used to make long-wearing tips for gold fountain-pen nibs.
- Osmium
- A member of the platinum group of metals and is commonly found in conjunction with these elements.
- Osmometry
- Determination of the average molecular weight of a dissolved substance from measurements of osmotic pressure.
- Osmosis
- Passage of solvent molecules from a dilute solution through a semipermeable membrane to a more concentrated solution.
- Osmotic Pressure
- Pressure which must be applied to a solution to prevent water from flowing in via a semipermeable membrane.
- Oxalic Acid
H2C2O4 A relatively strong organic acid, being about 10,000 times stronger than acetic acid. - Oxidation
- The loss of one or more electrons by an atom, molecule, or ion.
- Oxidation Half Reaction
- That part of a redox reaction that involves loss of electrons.
- Oxidation Number
- A number assigned to each atom to help keep track of the electrons during a redox-reaction.
- Oxidation Reaction
- A reaction where a substance loses electrons.
- Oxide
- A binary compound that contains oxygen in the -2 oxidation state.
- Oxidizing Agent
- Cause other substances to be oxidized in chemical reactions while they themselves are reduced.
- Oxyacid
- When one or more hydroxide (OH) groups are bonded to a central atom.
- Oxygen
- A colourless and odourless element that is essential for most life forms on earth. It is also the most abundant element on earth.
- Ozone
O3 Allotropic form of oxygen containing three atoms in the molecule. - P
- Phosphorus is a non-metallic element.
- Pa
- Protactinium is a radioactive element.
- Palladium
- A member of the platinum group of metals. It is silvery white in colour, is malleable and ductile, and is one of the most reactive in the group
- Paracetamol
- Another name for Acetaminophen.
- Paraffin Oil
- A term describing a whole series of saturated aliphatic hydrocarbons, also known as alkane hydrocarbons.
- Paraffin Wax
- Obtained as a residue from the distillation of petroleum.
- Parent Isotope
- An element that undergoes nuclear decay.
- Partial Miscibility
- Two liquids are considered partially miscible if shaking equal volumes of the liquids together results in a meniscus visible between two layers of liquid, but the volumes of the layers are not identical to the volumes of the liquids originally added.
- Partial Pressures
- The pressure exerted by a certain gas in a mixture.
- Particulate
- Composed of distinct particles.
- Parts Per Million
- Used to describe the amount of a trace element or substance present in the main substance.
- Patina
- A thin layer of corrosion products with a distinctive colouration that forms on a metal surface exposed to air and water.
- Pb
- Lead is a soft, malleable and ductile metallic element that has been known of and used since prehistoric times.
- PbCO3
- Lead II Carbonate, decomposes readily into Lead II Oxide and carbon dioxide at 200°C and can be reduced to lead using carbon monoxide.
- PbCrO4
- Lead II Chromate IV, used as a pigment due to strong yellow colour.
- PbO
- Lead monoxide varies in colour from pale yellow to brown, used in the manufacture of glass, paints, varnishes and glazes.
- PbO2
- Lead dioxide a dark brown powder, strong oxidizing agent.
- Pd
- Palladium is a member of the platinum group of metals. It is silvery white in colour, is malleable and ductile, and is one of the most reactive in the group
- Pearl Ash
- An old fashioned name for Potassium Carbonate.
- Pearlite
- A lamellar aggregate of ferrite and cementite.
- Peat
- Partially carbonized vegetable material, usually found in bogs.
- Pentane
C5H12 The fifth member of the paraffin series. Pentane exists in three isomeric forms. - Pentanol
C5H11OH A colourless liquid at room temperature with a choking aroma. - Peptide
- A short polymer made by linking together amino acid molecules.
- Percent Yield
- Equals experimental yield divided by theoretical yield times 100%.
- Perfluoromethane
- Alternative name for Tetrafluoromethane.
- peri-Ethylenenaphthalene
- Another name for Acenaphthene.
- Periodic Law
- The properties of the elements are periodic functions of their atomic numbers.
- Periodic Table
- The most commonly used arrangement of the periodic system.
- Peritectic
- An isothermal reversible reaction in metals where a liquid phase reacts with a solid phase to produce a single, different, solid phase upon cooling.
- Permangante of Potash
- Old fashioned name for Potassium Manganate VII.
- Permeability
- passage or diffusion of a gas, vapor, liquid, or solid through a material without physically or chemically affecting it.
- Term used to express various relationships between magnetic induction and magnetizing force; either absolute permeability or specific (relative) permeability.
- Perspex
- Tradename for Polymethyl Methacrylate Resin.
- Pesticide
- A chemical or biological agent that kills pests.
- Petrol
- A volatile, flammable liquid mixture of hydrocarbons, obtained from petroleum and used as a fuel for internal-combustion engines.
- Petroleum
- An oily, thick, flammable, usually dark coloured liquid that is a form of bitumen or a mixture of various hydrocarbons, occurring naturally in various parts of the world and often separated by distillation into petrol, naphtha, benzene, kerosene and paraffin.
- pH
- Measures the acidity of a solution. It is the negative logarithm of the concentration of the hydrogen ions in a substance.
- Pharmacognosy
- Identification, isolation, and characterization of biologically active substances in living things.
- Pharmacology
- The study of drugs, which includes determination of biological activity, biological effects, breakdown and synthesis, and delivery.
- Phase Boundary
- A surface where two samples of matter with different properties are in contact.
- Phase Change
- The change from gas to liquid to solid.
- Phenol
- Also known as carbolic acid. It is used as a strong disinfectant.
- Phenolic Resin
- A condensation reaction polymer. A key characteristic of phenolic resin is the ability to withstand high temperature, along with mechanical load with minimal deformation or creep. In other words, cured phenolic resin provides the product rigidity necessary to maintain structural integrity and dimensional stability even under severe conditions.
- Phenyl Methyl Ketone
- Alternative name for Acetophenone.
- Phenylamine
- Alternative name for Aniline.
- Philosopher′s Wool
- An old name for Zinc Oxide.
- Phlogisticated Air
- An old name for Nitrogen.
- Phlogiston
- A hypothetical elastic fluid which was seen as a metalizing and combustible principle.
- Phosphor Bronze
- An alloy of copper with 3.5 to 10% of tin and a significant phosphorus content of up to 1%.
- Phosphorescence
- The property of a material whereby it continues to emit visible light after it has been illuminated by ultraviolet light.
- Phosphoric Acid
H3PO4 An inorganic acid. - Phosphorus
- A non-metallic element.
- Photo Etching
- Chemical process of removing unwanted material in producing printed circuit boards.
- Photochemistry
- The study of the effects of light on chemical reactions.
- Pi Bonds
- A type of covalent bond in which the electron density is concentrated around the line bonding the atoms.
- Piano Wire
- High quality steel wire used for making springs.
- Piezoelectric
- Any material which provides a conversion between mechanical and electrical energy.
- Pinchbeck
- A cheap bronze alloy.
- Pitchblende
- The most important Uranium ore.
- Plane Wood
- A North American wood that resembles beech, durable in water but not in air.
- Plastic
- A solid material in the primary ingredient of which is an organic polymer of high molecular weight.
- Plasticizer
- A low molecular weight polymer additive that enhances flexibility and workability and reduces stiffness and brittleness.
- Platinum
- A lustrous, malleable and ductile metallic element.
- Plumbago
- The natural allotropic form of carbon.
- Plumbum
- Latin for lead, hence the symbol Pb.
- Plutonium
- A product of the radioactive decay of neptunium.
- Pm
- Promethium is a radioactive element of the rare earth series.
- Po
- Polonium is a radioactive element.
- pOH
- Measures the basicity of a solution. It is the negative logarithm of the concentration of the hydroxide ions.
- Point Defect
- A crystalline defect associated with one or, at most, several atomic sites.
- Polar Bond
- A bond involving electrons that are unequally shared.
- Polar Molecules
- Molecule with a partial charge.
- Polarization
- For an atom, the displacement of the centre of the negatively charged electron cloud relative to the positive nucleus, which is induced by an electric field.
- Polonium
- A radioactive element.
- Polyatomic Ion
- An ion formed by the loss or gain of electrons from a molecule or chemical group composed of two or more atoms.
- Polyatomic Molecule
- An uncharged particle that contains more than two atoms.
- Polycrystalline
- Referring to crystalline materials that are composed of more than one crystal or grain.
- Polyethylene
- Plastic used heavily in the packaging industry.
- Polymer
- A large molecule formed by the linking together of many smaller molecules known as monomers.
- Polymerization
- The process by which monomers are joined together to give a polymer.
- Polymerize
- To link smaller molecules together to form a larger molecule.
- Polymethyl Methacrylate Resin
- Commonly known as perspex or lucite, a transparent plastic.
- Polystyrene
- Expanded polystyrene was the first foamed polymer. It is the white rigid plastic used for thermal insulation and in flotation devices.
- Polytetrafluoroethylene
- Commonly known as Teflon, a thermoplastic polymer used for non-stick coatings and bearings.
- Polythene
- Alternative name for Polyethylene.
- Polyvinyl Acetate
- A colorless, thermoplastic, water soluble, resinous high polymer derived from the polymerization of vinyl acetate with a catalyst. Abbreviated as PVA.
- Polyvinyl Chloride
- Plastic used in many different forms. Commonly abbreviated as PVC.
- Ponderous Spar
- Old name for Barium Sulphate.
- Potash
- Old fashioned name for Potassium Carbonate made from the ashes of burnt wood.
- Potassium
- A soft, silvery coloured metal, which like other members of the alkali group of metals, is extremely reactive.
- Potassium Bromide
KBr A white crystalline salt used in photography. It was used in medicine as a sedative. - Potassium Carbonate
K2CO3 A white very soluble deliquescent salt. - Potassium Chloride
KCl White crystalline solid. - Potassium Fluoride
KF White crystalline solid. - Potassium Hydroxide
KOH A white deliquescent solid that dissolves in water to give an alkaline solution. - Potassium Iodide
KI White crystalline solid. - Potassium Manganate VII
KMnO4 Deep purple, crystalline, soluble salt. Dissolves in water to produce a strong oxidizing agent. Used as a disinfectant. - Potassium Nitrate
KNO3 The salt of potassium and nitric acid. Used in pyrotechnics, explosives, the manufacture of glass and as a fertilizer. - Potassium Oxide
K2O Yellowish white yo grey crystalline solid. - Potassium Permanganate
- Deep purple, crystalline, soluble salt.
- Potassium Peroxide
K2O2 Yellow or orange solid. - Potassium Sulphide
K2S White, yellow, red or brown. - Potassium Superoxide
KO2 Yellow crystalline solid. - Potin
- An ancient alloy of copper, zinc, lead and tin that was used to make coins.
- Power Density
- Characteristic parameter of a battery/electrical power source indicating its electrical power per unit weight or volume.
- ppm
- Abbreviation for Parts Per Million.
- Pr
- Praseodymium is a soft, white metal and a member of the lanthanide group of elements.
- Praseodymium
- A soft, white metal and a member of the lanthanide group of elements.
- Precipitate
- A solid that appears in the form of fine particles in what was previously a clear solution because of a chemical reaction.
- Precipitation Heat Treatment
- Artificial aging in which a constituent precipitates from a supersaturated solid solution.
- Prepreg
- A continuous fibre reinforcement pre-impregnated with a polymer resin which is then partially cured.
- Primary Bond
- Interatomic bonds that are relatively strong and for which bonding energies are relatively large.
- Promethium
- A radioactive element of the rare earth series.
- Propane
C3H8 A member of the alkane series, a colourless, odourless gas at room temperature. In liquid form it is often referred to as Liquid Petroleum Gas (LPG). - Propanol
CH3CH2CH2OH Used as an inexpensive alcohol. Also known as propyl alcohol. - Propanone
- Alternative name for Acetone.
- Propene
C3H6 A colourless highly flammable gas. - Propene Acid
- Alternative name for Acrylic Acid.
- Propenoic Acid
- Alternative name for Acrylic Acid.
- Propyl Alcohol
- Alternative name for Propanol.
- Propylene
- Alternative name for Propene.
- Protactinium
- A radioactive element.
- Protein
- A very large, naturally occurring polyamide formed from a selection of the 20 or so naturally occurring amino acids.
- Protium
- The lightest element of hydrogen of unit mass and the most prevalent in the universe.
- Prussic Acid
- A solution of Hydrogen Cyanide in water.
- Pt
- Platinum is a lustrous, malleable and ductile metallic element.
- PTFE
- Abbreviation of Polytetrafluoroethylene, a thermoplastic polymer used for non-stick coatings and bearings.
- Pu
- Plutonium is a product of the radioactive decay of neptunium.
- Pumice
- A light porous stone of mixed silicates.
- Pure Air
- An old name for oxygen
- Pure Substance</
|
