A compound formed by elements A and B has a cubic structure in which A atoms are at the corner of the cube and B atoms are at the face centres. Derive the fomula of the compound.

Explanation

As A atoms are present at the 8 corners of the cube, therefore , number of atoms of A in the unit cell `=1/8xx8=1`
As B atoms are present in the face centres of the 6 faces of the cube, therefore, number of atoms of B in the unit cell`=1/2xx6=3`
`therefore` Ratio of atoms A:B =1:3
Hence, the formula of the compound is `AB_3`