Lattice enthalpy

Lattice enthalpy is used to measure the strength of an ionic bond

• Things that affect :

  • size of atomic radius

  • Charge of atom

Lattice enthalpy: The change in energy to form 1 mole of an ionic lattice from its ions in the gaseous state under standard state conditions.

Enthalpy of Atomisation: The enthalpy change when 1 mole of gaseous atoms are formed from its constituents in standard states.

First electron affinity: When one mole of gaseous atoms each gains 1 mol of electrons to form one mole of gaseous ions with a -1 charge in standard conditions.

First electron affinity is always exothermic but the second one and the ones after are endothermic since energy is required to overcome the repulsion of the two negative charges when adding additional electrons to an already negatively charged ion.