A cubic unit cell has one atom on each corner and one atom on each body diagonal. The number of atoms in the unit cell is

Answer

5

Explanation

Contribution of atoms on the corners = `8 xx 1/8 = 1`
Since atoms on the body diagonal are not shared by any other unit cell there are four body diagonals, their contribution per unit cell = 4.
`:.` Total number of atoms in the unit cell = 4 + 1 = 5.