AQA A Level Chemistry- Definitions Paper 2 with complete solutions

spectator ion ion which does not take part in a reaction ionic lattice ionic solid formed with the ions held in a three-dimensional framework coordinate bond a bond containing a shared pair of electrons with both electrons supplied by one atom allotropes different forms of the same element in the same physical state (diamond and graphite) electronegativity the power of an atom to attract the pair of electrons in a covalent bond induced dipole a temporary dipole caused by electrons being more distributed to one side of an atom than the other and another molecule approaching this side will have its electrons repelled enthalpy change heat energy change at constant pressure activation energy minimum amount of energy needed for reacting particles to successfully collide standard enthalpy value the delta H values for enthalpy changes of specific reactions measured under standard conditions conservation of energy law stating energy cannot be created or destroyed, just converted from one form to another Hess' Law law stating the enthalpy change for a chemical reaction is independent of the route taken and depends only on the initial and final states mean bond enthalpy measure of energy required to break one mole of a covalent bond measured in the gaseous state averaged across many compounds containing the bond dynamic equilibrium where you have a steady state because the rates of the forward reaction and reverse reaction are the same