Question

The distance between the body centred atom and a corner atom in sodium (a = 4.225 Å) is.

• A. 3.66 Å
• B. 3.17 Å
• C. 2.99 Å
• D. 2.54 Å

Answer 1

Answer: (A)

3.66 Å

Answer 2

Sodium has bcc structure.

The distance between body centre and a corner $= \frac{\sqrt{3}a}{2}$

$= \frac{\sqrt{3} \times 4.225}{2} = 3.66Å$