Question

Copper crystallises in a face-centred cubic lattice with unit edge length of 361 pm. What in the radius of copper atom in pm?

Options

• 157

• 181

• 108

• 128

Answer 1

128

Explanation:

Copper crystallises in a face-centred cubic lattice.

Atomic radius (r) = `9/(2sqrt(2)) = 316/(2 xx 1.414)` = 127.6

= 128 pm.