Import Question JSON

$\text{HINT: Lattice energy } \propto \frac{\text{q}^+\text{q}^-}{\text{r}} \text{Explanation:} \text{Step 1:} \text{(a).} \text{As the charge on cation is increased the lattice energy increases if the anion is the same.} \text{In the case of AlF}_3\text{, the charge on Al is +3 and in the case of MgF}_2 \text{ charge on Mg is +2. Hence, as the cation charge increases the lattice energy also increases.} \text{(b).} \text{If cation is the same, then as the charge on anion increases, the lattice energy also increases.} \text{In the case of Li}_3\text{N and Li}_2\text{O, the cation is the same that is Li}^+\text{. As anion charge increases, lattice energy also increases. Nitrogen has a -3 charge, and oxygen has a -2 charge. Hence, Li}_3\text{N lattice energy is more than Li}_2\text{O.} \text{(c).} \text{Lattice energy is inversely proportional to inter-ionic distance. In NaCl and LiF, the inter-ionic distance is less in the case of LiF than NaCl. Hence, LiF has high lattice energy than NaCl.} \text{(d).} \text{In TiC and ScN, the internuclear distance is almost the same then lattice energy is explained by the charge factor.} \text{In TiC, the charge on Ti is +4 and on C is -4, and in ScN, the charge on Sc is +3 and on N is -3. Hence, TiC has more charge than ScN. Thus, the lattice energy of TiC is more than ScN.} \text{Step 2:} \text{The incorrect order is NaCl > LiF because LiF has more lattice energy than NaCl.}$