Lattice Energy (Enthalpy)
Concept and Applications
Rafa Muñoa
Lizardi Institutua
Zarautz
Definition
The lattice formation enthalpy is the enthalpy change when 1 mole of solid crystal is formed from its scattered gaseous ions. Lattice formation enthalpies are always negative.
Na+ (g) + Cl- (g) = NaCl (s)
Lattice enthalpy is a measure of the strength of the forces between the ions in an ionic solid. The greater the lattice enthalpy, the stronger the forces.
Rafa Muñoa
Lizardi Institutua
Zarautz
Factors affecting lattice enthalpy
The two main factors affecting lattice enthalpy are
(a) the charges on the ions and
(b) the ionic radii (which affects the distance between the ions).
Rafa Muñoa
Lizardi Institutua
Zarautz
Factors affecting lattice enthalpy
The two main factors affecting lattice enthalpy are (a) the charges on the ions and
(b) the ionic radii (which affects the distance between the ions).
Rafa Muñoa
Lizardi Institutua
Zarautz