AQA A level Chemistry Enthalpy Definitions Questions and Answers

AQA A level Chemistry Enthalpy Definitions Questions and Answers Enthalpy change of formation The enthalpy change when one mole of a compound is formed from its constituent elements in their standard states under standard conditions Bond dissociation enthalpy The enthalpy change when all the bonds of the same type are broken in one mole of gaseous molecules Enthalpy change of atomisation of an element The enthalpy change when one mole of gaseous atoms is formed from an element in its standard state Enthalpy change of atomisation of a compound The enthalpy change when one mole of a compound in its standard state is converted to gaseous atoms First ionisation enthalpy The enthalpy change when one mole of gaseous 1+ ions is formed from one mole of gaseous atoms under standard conditions Second ionisation enthalpy The enthalpy change when one mole of gaseous 2+ ions is formed from one mole of gaseous 1+ ions under standard conditions First electron affinity The enthalpy change when one mole of gaseous 1- ions is formed from one mole of gaseous atoms Second electron affinity The enthalpy change when one mole of gaseous 2- ions is formed from one mole of gaseous 1- ions Enthalpy change of hydration The enthalpy change when one mole of aqueous ions is formed from gaseous ions Enthalpy change of solution The enthalpy change when one mole of an ionic substance dissolves in enough solvent to form an infinitely dilute solution Enthalpy change of combustion The enthalpy change when one mole of a substance is burned completely in excess oxygen with all reactants and products in their standard states under standard conditions Lattice enthalpy of formation The enthalpy change when one mole of a solid ionic compound is formed from its gaseous ions under standard conditions Lattice enthalpy of dissociation The enthalpy change when one mole of a solid ionic compound is completely dissociated into its gaseous ions under standard conditions