How many types of body centred unit cells are possible?

Options

A. Three
B. Two
C. Four
D. Seven

Explanation

To determine how many types of body-centered unit cells are possible, we can follow these steps:

### Step 1: Understand Body-Centered Unit Cells (BCC)
A body-centered unit cell (BCC) is a type of crystal structure where there is one atom at each corner of the cube and one atom at the center of the cube. This arrangement contributes to the overall properties of the solid.

### Step 2: Identify Lattice Systems
Lattice systems are classifications of crystal structures based on their symmetry and geometry. The main lattice systems include:
- Cubic
- Tetragonal
- Orthorhombic
- Hexagonal
- Monoclinic
- Triclinic

### Step 3: Determine Which Lattice Systems Can Accommodate BCC
Not all lattice systems can accommodate body-centered unit cells. The two lattice systems that can accommodate BCC structures are:
1. Monoclinic
2. Triclinic

### Step 4: Conclusion
Thus, the types of body-centered unit cells that are possible correspond to the two lattice systems identified above.

### Final Answer
**There are 2 types of body-centered unit cells possible, which are found in the Monoclinic and Triclinic lattice systems.**

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