For two ionics solids CaO and Kl, identify the wrong statement among the following .

Options

A. CaO has high melting point
B. Lattice energy of CaO is much larger than that of Kl
C. Kl has high melting point
D. Kl is soluble in benzene

Answer

To identify the wrong statement among the given options regarding the ionic solids calcium oxide (CaO) and potassium iodide (KI), we can follow these steps:

### Step 1: Understand the properties of ionic solids
Ionic solids are characterized by their high melting points and lattice energies. The lattice energy is the energy released when gaseous ions combine to form an ionic solid. Higher lattice energy typically corresponds to a higher melting point.

### Step 2: Compare the lattice energy of CaO and KI
Calcium oxide (CaO) consists of Ca²⁺ and O²⁻ ions, while potassium iodide (KI) consists of K⁺ and I⁻ ions. The charges on the ions in CaO are higher (2+ and 2-) compared to those in KI (1+ and 1-). This leads to a greater lattice energy for CaO.

### Step 3: Analyze the melting points
Due to its higher lattice energy, CaO has a higher melting point than KI. Therefore, any statement claiming that KI has a high melting point compared to CaO would be incorrect.

### Step 4: Evaluate the solubility of KI in benzene
Potassium iodide (KI) is an ionic compound and is generally soluble in polar solvents like water, but it is insoluble in non-polar solvents like benzene. Therefore, any statement claiming that KI is soluble in benzene would also be incorrect.

### Step 5: Identify the wrong statement
Given the analysis:
1. **Calcium oxide has a high melting point** - This statement is correct.
2. **The lattice energy of calcium oxide is much larger than potassium iodide** - This statement is also correct.
3. **Potassium iodide has a high melting point** - This statement is incorrect.
4. **Potassium iodide is soluble in benzene** - This statement is also incorrect.

Thus, the wrong statements are:
- Potassium iodide has a high melting point.
- Potassium iodide is soluble in benzene.

### Final Answer
The wrong statement is: **Potassium iodide has a high melting point.**