Hexagonal close packing is found in crystal lattice of :

Options

A. Na
B. Mg
C. Al
D. None of these

Answer

To solve the question regarding which crystal lattice exhibits hexagonal close packing (hcp), we can follow these steps:

### Step 1: Understand Hexagonal Close Packing (hcp)
Hexagonal close packing is a type of crystal lattice arrangement where atoms are closely packed in a hexagonal shape. In this arrangement, each atom is surrounded by 12 other atoms, which gives it a coordination number of 12.

**Hint:** Remember that coordination number refers to the number of nearest neighbors surrounding an atom in a crystal lattice.

### Step 2: Identify the Characteristics of hcp
In hcp, the atoms are arranged in layers. The first layer has atoms arranged in a hexagonal pattern, and the second layer fits into the depressions of the first layer. This stacking continues, leading to a very efficient packing of atoms.

**Hint:** Visualizing the arrangement of atoms in layers can help you understand how hcp works.

### Step 3: Relate hcp to Common Elements
Common elements that exhibit hexagonal close packing include metals such as magnesium (Mg), zinc (Zn), and cadmium (Cd). Among these, magnesium is a well-known example.

**Hint:** Think about the properties of metals and which ones are known for their close packing structures.

### Step 4: Conclusion
Based on the understanding of hexagonal close packing and its relation to specific elements, we can conclude that magnesium (Mg) exhibits hexagonal close packing in its crystal lattice.

**Final Answer:** Hexagonal close packing is found in the crystal lattice of magnesium (Mg).

### Summary of Steps:
1. Understand the concept of hexagonal close packing (hcp).
2. Identify the characteristics of hcp.
3. Relate hcp to common elements, focusing on magnesium.
4. Conclude that magnesium exhibits hcp.