Aluminium crystallizes in an fcc structure. Atomic radius of the metal is 125 pm.
What is the length of the edge of the unit cell ?

Explanation

To find the length of the edge of the unit cell for aluminum, which crystallizes in a face-centered cubic (FCC) structure, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the relationship between atomic radius and edge length in FCC:**
In a face-centered cubic (FCC) structure, the relationship between the atomic radius (r) and the edge length (a) is given by the formula:
\[
4r = \sqrt{2}a
...