The type of void present at the centre of the ccp unit cell is

Options

A. Trigonal void
B. Tetrahedral void
C. Octahedral void
D. All of these

Answer

To solve the question regarding the type of void present at the center of the CCP (Close Packed Cubic) unit cell, we can follow these steps:

### Step 1: Understand the CCP Unit Cell
The CCP unit cell is also known as the Face-Centered Cubic (FCC) structure. It consists of atoms located at each corner of the cube and at the centers of all the faces.

**Hint:** Remember that CCP is synonymous with FCC.

### Step 2: Identify Types of Voids
In a CCP unit cell, there are two main types of voids:
1. Tetrahedral voids
2. Octahedral voids

**Hint:** Recall that tetrahedral voids and octahedral voids are the two types of voids found in crystal structures.

### Step 3: Locate the Voids
- **Tetrahedral Voids:** These are located at positions that are not at the center of the unit cell. Specifically, there are two tetrahedral voids along each body diagonal of the cube.
- **Octahedral Voids:** These are located at the center of the unit cell and at the midpoints of the edges. The body center of the cube is one such location.

**Hint:** Focus on the positions of the voids in relation to the unit cell structure.

### Step 4: Determine the Void at the Center
Since the question specifically asks for the type of void present at the center of the CCP unit cell, we need to identify which void occupies the body center.

The body center of the CCP unit cell is where the octahedral void is located.

**Hint:** The body center is a key location for identifying void types in cubic structures.

### Step 5: Conclusion
Based on the analysis, the type of void present at the center of the CCP unit cell is the **octahedral void**.

**Final Answer:** The type of void present at the center of the CCP unit cell is the **octahedral void**.

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