enthalpy change definitions

enthalpy of formation

enthalpy change when 1 mole of substance is formed from its constituent elements with all substances in their standard states

enthalpy of combustion

enthalpy change when 1 mole of a substance undergoes complete combustion in oxygen with all substances in standard statss

enthalpy of neutralisation

enthalpy change when 1 mole of water is formed in a reaction between an acid and alkali under standard conditions

first ionisation energy

enthalpy change when each atom in one mole of gaseous atoms loses one electron to form 1 mole of gaseous 1+ ions

2nd ionisation energy

enthalpy change when each ion in 1 mole of gaseous 1+ ions loses 1 electron to form 1 mole of gaseous 2+ ions

1st electron affinity

enthalpy change when each atom in 1 mole of gaseous atoms gains 1 electron to form 1 mole of gaseous 1- ions

2nd electron affinity

enthalpy change when each ion in 1 mole of gaseous 1- ions gains one electron to form one mole of gaseous 2- ions

enthalpy of atomisation

enthalpy change when 1 mole of gaseous atoms is produced from an element in its standard states

hydration enthalpy

enthalpy change when 1 mole of gaseous ions become hydrated (dissolved in water)

enthalpy of solution

enthalpy change when 1 mole of an ionic solid dissolves in an amount of water large enough so that the dissolved ions are well separated and do not interact with each other

bond dissociation enthalpy

enthalpy change when 1 mole of covalent bonds is broken in the gaseous state

lattice enthalpy of formation

enthalpy change when 1 mole of a solid ionic compound is formed from into its constituent ions in the gas phqse

lattice enthalpy of dissociation

enthalpy change when 1 mole of a solid ionic compound is broken up into its constituent ions in the gas phase

enthalpy of vaporisation

enthalpy change when 1 mole of a liquid is turned into a gas

enthalpy of fusion

enthalpy change when 1 mole of a solid is turned into a liquid