Question

Xenon crystallizes in the face-centred cubic lattice and the edge of the unit cell is 620 pm. What is the nearest neighbor distance and what is the radius of xenon atom?

• A. 438pm
• B. 240pm
• C. 135pm
• D. 98pm

Answer 1

The correct option is A 438pm

Use Pythagoras theorem for Nearest neighbour distance formula.

Nearest neighbour distance = $\frac{1}{2}\times \sqrt{2}\times a$

= $\frac{1}{2}\times \sqrt{2}\times 620$ = 438 pm