Frenkel defect is also known as ……… .

Options

A. Soichiometric defect
B. dislocation defect
C. impurity defect has no effect on the density of the substance
D. non- stoichometric defect

Explanation

To answer the question "Frenkel defect is also known as ………", we can follow these steps:

### Step 1: Understand the Definition of Frenkel Defect
A Frenkel defect is a type of point defect in a crystal lattice where an atom or ion leaves its normal lattice site and occupies an interstitial site. This creates a vacancy at the original site.

### Step 2: Identify Alternative Names for Frenkel Defect
The Frenkel defect is also referred to as:
- **Dislocation defect**: This term highlights the movement of atoms from their original positions.
- **Stoichiometric defect**: This name indicates that the defect does not change the overall stoichiometry of the compound, meaning the ratio of the different types of atoms remains the same.

### Step 3: Analyze the Characteristics of Frenkel Defect
- It does not affect the density of the material because the total number of atoms remains unchanged; they are just relocated within the lattice.
- It is significant in understanding the properties of ionic solids and their behavior under certain conditions.

### Conclusion
Thus, the Frenkel defect is also known as:
1. **Stoichiometric defect**
2. **Dislocation defect**

Both terms are correct in describing the Frenkel defect.

### Final Answer:
Frenkel defect is also known as **stoichiometric defect** and **dislocation defect**.

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