Enthalpy Definitions

Bond Dissociation Enthalpy

Enthalpy change when one mole of covalent bonds is brokens in the gaseous state.

Enthalpy of Formation

Enthalpy change when one mole of a substance is formed from its constituent elements with all substances in their standard states.

Lattice Enthalpy of Dissociation

Enthalpy change when one mole of a solid ionic compound is broken up into its constituent ions in the gas phase.

Enthalpy of Combustion

Enthalpy change when one mole of a substance undergoes complete combustion in oxygen with all substances in standard states.

Hydration Enthalpy

Enthalpy change when one mole of gaseous ions become hydrated.

Electron Affinity

Enthalpy change when each atom in one mole of gaseous atoms gains an electron to form one mole of gaseous 1- ions.

Lattice Enthalpy of Formation

Enthalpy change when one mole of a solid ionic compound is formed from its constituent ions in the gas phase.

Enthalpy of Atomisation

Enthalpy change when one mole of gaseous atoms are formed from an element in its standard state.

Enthalpy of Ionisation 

Enthalpy change when each atom in one mole of gaseous atoms lose an electron to form one mole of gaseous 1+ ions.

Enthalpy of Solution

Enthalpy change when one mole of a solid ionic compound is dissolved in an amount of water large enough so that the dissolved are well separated and do not interact with each other.