Definition from manual

Acid ( Arrhenius )

Produces hydrogen ion by dissociation in water

Acid ( Bronsted-Lowry )

Proton ( hydrogen ion ) donor

Acidic oxide

Oxide that lowers PH in water

Activation energy

Minimum energy needed for colliding particles to react

Addition polymerisation

Monomers combining to form a large molecule

Adsorption

The method if attachment of gaseous or liquid molecules to solid surface

Atomic absorption spectrometry

Instrumental method used to analyse water for heavy metals

Atomic number

Number of protons in nucleus

Atomic orbital

Region around nucleus in which there is high probability of finding an electron element

Atomic radius

Half the distance between the centre of singly bonded atoms of the same element

Atomic sub-level

A sub-division of main energy level consisting of one or more orbitals of the same energy

Auto-ignition

Tendency to premature ignition

Avogardo’s law

Equal volumes of gases contain equal numbers of molecules under same conditions of temperature and pressure

Base (Arrhenius)

Produces OH- as only anion in aqueous solution

Base (bronsted Lowry)

Protons acceptor

Biochemical oxygen demand

amount of oxygen consumed in ppm. When sample kept in dark for 5 days at 20c

Bond energy

Average energy required to break 1mole of bonds into separate atoms in the gaseous state

Boyles law

Pressure inversely proportional to volume for definite más of gas at constant temp or PV=k

Catalyst

Substance that alters the rate of a reaction and is not used up

Catalytic cracking

Splitting of long chain molecules by heat and catalysts

Catalytic poison

Substance that blocks the active site of a catalyst and stops it from working

Charles law

V/T = k

Chemical equilibrium

Rate of forward reaction = rate of reverse reaction

Condensation reaction

Production of a more complex molecule with a formation of an unsaturated compound or double bond by loss of a small molecule

Chromatography

Separation of a mixture of components based on their relative attractions for a stationary phase while carried by a mobile phase

Conjugated acid (bronsted Lowry)

Produced by gain of one proton

Conjugate pair

Acid base differing by proton

Covalent bond

Sharing of one or more pairs of electrons

Crystals

Regular solids made up of particles with faces of intersecting at fixed angles

Dobereiners triads

Elements with similar properties in groups of three

Effective collision

Results in a reaction

Electrolysis

Chemical reaction caused by electric current passing through an electrolyte

Electronegativity

Measure of relative attraction for shared electrons

Element

Can not be broken down into anything simpler

Emulsion

A suspension of oil droplets in water

Energy level

Shell which electrons of equal energy’s occupy

Eutrophication

Excess plant growth caused by excess nutrients in water

Excited state

Higher energy state

Feedstock

Modified and purified raw materials

First ionisation energy

Minimum energy to remove the most loosely bond electron from an isolated gaseous atom in its ground state

Flocculation

Clumping of suspended solids in water

Greenhouse factor

Stating its influence on the greenhouse effect compared with carbon dioxide

Greenhouse effect

Blocking the escape of radiation by gases in the atmosphere