Calculate the lattice energy (in Units kJ mol^-1) for ZnO crystal using Eq. 3.4 based on electrostatic model and using a Born-Haber cycle. Compare the two answers and comment on any difference.
Useful data:
Medelung constant (A) = 1.6411
Born Constant (n) = 8
Internuclear distance (a) = 199 pm
Zn(s) + ½ O2(g) → ZnO(s) ∆H_f = - 350.5 kJ mol^-1
Zn(s) → Zn(g) ∆HS = 130.4 kJ mol^-1
Zn(g) → Zn⁺(g) I(Zn) = 906.3 kJ mol^-1
Zn⁺(s) → Zn²⁺(g) I(Zn+) = 1733 kJ mol^-1
½ O2(g) → O(g) ½ ∆H_d = 248.5 kJ mol^-1
O(g) → O^- (g) E_A(O) = 141 kJ mol^-1
O^-(g) → O^2-(g) EA(O^-) = - 780 kJ mol^-1

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