Question

For two ionic solids CaO and KI, identify the wrong statement amongst the following :

• A. The lattice energy of CaO is much large than that of KI
• B. KI is more soluble in water
• C. KI has higher melting point
• D. CaO has higher melting point

Answer 1

Answer: (C)

KI has higher melting point

Answer 2

CaO has higher lattice energy because of higher charge on ${Ca^{2+}}$ and ${O^{2-}}$, which results in higher attraction. KI is more soluble in water because of low lattice energy and higher hydration energy. Clearly (c) is wrong because CaO has higher melting point as compared to KI.