Question

The unit cell of a body-centred cubic system contains ______ atoms.

Answer 1

The unit cell of a body-centred cubic system contains two atoms.

Explanation:

In a body-centred cubic (bcc) unit cell, there are 8 corner atoms. Each corner atom is shared by 8 unit cells, so each contributes `1/8`, i.e., `8 xx 1/8 = 1` atom.

1 atom at the centre of the cube fully belongs to the unit cell, i.e., 1 atom.

∴ Total atoms in bcc unit cell = 1 + 1 

= 2