Question

Born-Haber cycle is used to determine :

• A. electron affinity
• B. lattice energy
• C. crystal energy
• D. all of these

Answer 1

Answer: (D)

Born Haber cycle is used to determine lattice energy $(LE)$ of ionic crystals to other thermodynamics data [i.e., ionisation energy $(IE)$, electron affinity $(EA)$ dissociation energy $(D)$ etc.)
e.g., let us consider formation of $NaCl$
$Na(s)+$ sublimation energy $(S)⟶Na(g)$
$\frac{1}{2}C{l}_2(g)+\frac{D}{2}⟶Cl(g)$
$Na(g)+IE⟶N{a}^{+}(g)+e^{-}$
$Cl(g)+e^{-}⟶C{l}^{-}(g)+EA$
$N{a}^{+}(g)+C{l}^{-}(g)⟶NaCl+LE$
$\Delta H_f=S+\frac{1}{2}D+IE+EA+LE$