Total volume of atoms present in a face centred cubic unit cell of a metal is (r = radius of atom) (a) r (b) r (c) r (d) r

For the FCC crystals: Number of atom = 4 Volume of single atoms = 3 4 3 r Total volume of atoms = 3 3 4 16 4 3 3 r r x Hence the correct answer is option (d)