The intermetallic compound LiAg crystallizes in cubic lattice in which both lithium and silver have co-ordination number of eight. The crystal class is

Options

A. simple cubic
B. body centered cubic
C. face - centered cubic
D. none of these

Answer

To determine the crystal class of the intermetallic compound LiAg, we need to analyze the information provided about its structure and coordination number. Here’s a step-by-step solution:

### Step 1: Understand Coordination Number
The coordination number is defined as the number of nearest neighboring atoms surrounding a central atom in a crystal lattice.

**Hint:** Recall that different types of crystal lattices have specific coordination numbers associated with them.

### Step 2: Identify the Coordination Number
The problem states that both lithium (Li) and silver (Ag) in the compound LiAg have a coordination number of 8.

**Hint:** Coordination numbers help identify the type of crystal structure.

### Step 3: Analyze Crystal Structures
Now, let's look at the common types of cubic crystal structures and their respective coordination numbers:
- **Simple Cubic (SC):** Coordination number = 6
- **Body-Centered Cubic (BCC):** Coordination number = 8
- **Face-Centered Cubic (FCC):** Coordination number = 12

**Hint:** Knowing the coordination numbers of different cubic structures is crucial for identifying the correct one.

### Step 4: Match Coordination Number with Crystal Structure
Since both lithium and silver have a coordination number of 8, we can conclude that the structure of LiAg corresponds to the Body-Centered Cubic (BCC) lattice.

**Hint:** Look for the cubic structure that matches the coordination number given in the problem.

### Step 5: Conclusion
Based on the analysis, the crystal class of the intermetallic compound LiAg is **Body-Centered Cubic (BCC)**.

**Final Answer:** The crystal class is Body-Centered Cubic (BCC).