JEE Main · 2019 · 12 Apr 2019 · Shift 2 · Solid State

The ratio of number of atoms present in a simple cubic, body centered cubic and face centered cubic structure are, respectively :

Answer: (A)

Solution

A simple cubic cell keeps only corner atoms,

8 \times \frac{1}{8} = 1

. A body-centred cell adds one atom at the centre,

8 \times \frac{1}{8} + 1 = 2

. A face-centred cell adds six half-shared face atoms,

8 \times \frac{1}{8} + 6 \times \frac{1}{2} = 4

. So the ratio is

1 : 2 : 4

JEE Main · 2019 · 12 Apr 2019 · Shift 2 · Single correct option