Which of the following has Frenkel defect?

Options

A. Sodium chloride
B. Graphite
C. Silver bromide
D. Diamond

Explanation

To determine which of the given options has a Frenkel defect, we need to understand what a Frenkel defect is and the conditions under which it occurs.

### Step-by-Step Solution:

1. **Understanding Frenkel Defect**:
- A Frenkel defect occurs when an ion (usually a cation) leaves its normal lattice position and occupies an interstitial site, creating a vacancy in the lattice. This defect is common in ionic compounds where the cations and anions differ significantly in size.

2. **Conditions for Frenkel Defect**:
- The ionic compound should have a low radius ratio (R-radius ratio).
- There should be a significant size difference between cations and anions.
- The ions should have a low coordination number.

3. **Identifying Candidates**:
- We need to look at the given options (not provided in the question, but let's assume common ionic compounds) and check if they meet the criteria for Frenkel defects.
- Common examples of ionic compounds that exhibit Frenkel defects include:
- Zinc Sulfide (ZnS)
- Silver Bromide (AgBr)
- Silver Iodide (AgI)

4. **Analyzing the Options**:
- Among the candidates, both Silver Bromide (AgBr) and Silver Iodide (AgI) are known to exhibit Frenkel defects due to their significant size difference between Ag+ and Br- or I- ions.
- Zinc Sulfide (ZnS) can also exhibit Frenkel defects, but it is less common compared to the silver halides.

5. **Conclusion**:
- Based on the analysis, the correct answer to the question "Which of the following has Frenkel defect?" would be **Silver Iodide (AgI)** and **Silver Bromide (AgBr)**.

### Final Answer:
- The correct options that exhibit Frenkel defect are **Silver Iodide (AgI)** and **Silver Bromide (AgBr)**.