Question

What would be the empirical formula of a compound having a unit cell containing A ion shared equally at the corner of the cube and B ion on the centre of faces of the cube?

Answer 1

Given: A = At the corner of the cube.

B = At the centre of the faces of the cube.

Hence, the unit cell is a face-centred cubic system (fee).

Now, A at the corner

= `1/8 xx 8`

= 1 ion

and B at the centre of the face

= `6 xx 1/2`

= 3 ions

∴ The empirical formula of a compound is AB₃.