Silver crystallises with face-centred cubic unit cells. Each side of the unit cell has a length of 409 pm. What is the radius of an atom of silver? (Assume that each face atom is touching the four corner atoms.)
Given : a = 409 pm r = ?
For fcc unit cell, the formula is
or r = = =
r = 144.62
Radius of an atom of silver = 144.62 pm