Question

Silver crystallises in fcc structure, if edge length of unit cell is 316.5 pm. What is the radius of silver atom?

Options

• 121.91 pm

• 111.91 pm

• 137.04 pm

• 158.25 pm

Answer 1

111.91 pm

Explanation:

Given,

Edge length of unit cell (a) = 316.5 pm

For fcc we know,

Radius (r) = `"a"/(2sqrt2)`

`= 316.5/(2sqrt2)`pm

`= 158.25/1.414` pm

= 111.91 pm