Here is a list of all the definitions you have to know for A2 Chemistry paper 2. You will do well to memorise all of them.
Acid - proton donor
Activation energy - min. energy required for a collision to be effective
Addition polymer - Polymer formed from monomers with a C=C bond.
Atomic radius - Half the distance btw the centres of a pair of atoms.
Base - proton acceptor
Bond energy - Energy required to break 1 mol of a covalent bond in the gaseous state.
Bond length - Distance btw the centres of two nuclei of covalently bonded atoms.
Carbocation - An organic ion in which one of the carbon atoms has a positive charge.
Chiral centre - Atom that is bonded to 4 different groups.
Covalent bonding - Chemical bond formed by the electrostatic attraction btw the nuclei of two atoms and the shared pair of electrons.
Dative bond - Covalent bond in which both e- in the bond originate from one atom in the bond.
Disproportionation - Redox reaction in which the oxidation no. of some atoms of an element increase and others of the same element decrease.
Dynamic equilibrium - A situation where the concentration of products & reactants remain the same because the rates of forward and backward reactions are equal when temperature and pressure are constant.
Electronegativity - The ability of an atom to attract the shared pair of e- towards itself.
Enthalpy change of first IE - Enthalpy change when 1 mole of electrons is removed from 1 mole of atoms in the gaseous state.
Giant structure - A structure in which the atoms form an extended geometrical arrangement.
Free radical - Chemical species with unpaired electrons
Ionic bond - Electrostatic attraction btw +vely charged ions and -vely charged ions.
Lone pair - A pair of electrons in the outer shell of an atom that are not involved in bonding.
Metallic bond - Electrostatic attraction btw positive metal ions and delocalised electrons.
Nucleon number - Total number of p & n in the nucleus of an atom.
Nucleophile - Electron pair donor
Planar - Molecule where all atoms are in the same plane.
Polar - Molecule with asymmetric charge distribution.
Standard Enthalpy Change of Combustion - 1 mol burnt completely in oxygen in standard states.
Standard Enthalpy Change of Formation - 1 mol formed from constituent elements
Standard Enthalpy Change of Neutralisation - 1 mol of water formed from acid and alkali.
Optical isomerism / Stereoisomerism - Same structural formulae but diff arrangement of atoms in space.