Sodium chloride , NaCl , usually crystallizes in a face - centered cubic lattice. How many ions are in contact with any single `Na^(+)` ion ?

Options

A. 4
B. 6
C. 8
D. 1

Answer

To determine how many ions are in contact with a single Na⁺ ion in sodium chloride (NaCl) crystallized in a face-centered cubic (FCC) lattice, we can follow these steps:

### Step 1: Understand the Crystal Structure
Sodium chloride crystallizes in a face-centered cubic (FCC) lattice structure. In this arrangement, the sodium ions (Na⁺) and chloride ions (Cl⁻) alternate in the lattice.

**Hint:** Familiarize yourself with the basic structure of FCC lattices and how ions are arranged within them.

### Step 2: Identify the Coordination Number
In an FCC lattice, each ion is surrounded by ions of the opposite charge. The coordination number refers to the number of nearest neighbor ions that surround a given ion.

**Hint:** Coordination number is a key concept in understanding how ions interact in a crystal lattice.

### Step 3: Determine the Surrounding Ions for Na⁺
For a single Na⁺ ion in the FCC lattice of NaCl, it is surrounded by 6 Cl⁻ ions. This means that there are 6 ions in contact with any single Na⁺ ion.

**Hint:** Visualize the arrangement of ions in the lattice to see how many are directly adjacent to the Na⁺ ion.

### Step 4: Conclusion
Thus, the number of ions in contact with any single Na⁺ ion in sodium chloride is 6.

**Final Answer:** The answer is 6.

### Summary of Steps:
1. Understand the FCC structure of NaCl.
2. Identify the coordination number.
3. Determine the number of surrounding ions for Na⁺.
4. Conclude that there are 6 ions in contact with Na⁺.