Define : (a) Enthalpy of atomization (b) Lactic enthalpy.

Explanation

Enthalpy of atomization : It is defined as the enthalpy change accompanying the breaking of one mole of a substance completely into its atoms in the gas phase.
`H_(2)(g) rarr 2H(g) , Delta_(s)H^(@) = 435.0 kJ mol^(-1)`
Lattice enthalpy : It is the enthalpy change which occurs when one mole of an ionic compound dissociates into its gaseous ionic state.
`NaCl(s) rarr Na^(+) (g) + Cl^(-) (g) , Delta H = +788 ks//mol`.