Which one of the following compounds can show Frenkel defect ?

Options

A. ZnS
B. AgCl
C. Agl
D. All of these

Answer

To determine which compound can show a Frenkel defect, we need to follow these steps:

### Step-by-Step Solution:

1. **Understand the Concept of Frenkel Defect**:
- Frenkel defect is a type of point defect in ionic solids where a cation leaves its normal lattice site and occupies an interstitial site. This typically occurs in ionic compounds where there is a significant size difference between cations and anions.

2. **Identify the Characteristics of Compounds that Exhibit Frenkel Defect**:
- Frenkel defects are usually observed in ionic compounds, particularly when the cation is smaller than the anion. The smaller cation can easily move to an interstitial site.

3. **Evaluate the Given Options**:
- The question provides several compounds. We need to analyze each one to see if they are ionic and if they have a significant size difference between their cations and anions.

4. **Analyze Each Compound**:
- For example, consider the following:
- **Zinc Sulphide (ZnS)**: Zinc ion (Zn²⁺) is smaller than the sulfide ion (S²⁻).
- **Silver Chloride (AgCl)**: Silver ion (Ag⁺) is smaller than the chloride ion (Cl⁻).
- **Sodium Iodide (NaI)**: Sodium ion (Na⁺) is smaller than the iodide ion (I⁻).
- All these compounds have smaller cations compared to their respective anions.

5. **Conclusion**:
- Since all the compounds listed exhibit the characteristics necessary for a Frenkel defect, they can all potentially show this defect. Therefore, the correct answer would be that all the provided options can show Frenkel defects.

### Final Answer:
All the compounds listed in the options can show Frenkel defect.

---