If a solid 'AB','A' atoms have ccp arrangement and B atoms occupy all the octahedral sites. If all the face centred atoms along one of the axes are removed, then what will be the resultant stoichiometry of the compound?

Explanation

In ccp type structure, there are 8A at the corners of the cube and 6A atoms on the face centres. If all the face centred atoms along one of the axes are removed, it means removal of 2A atoms. Therefore, only 4 atoms will be left on faces .
No. of A atoms per unit cell = `8 xx 1/8 + 4 xx 1/2 = 3`
No. of B atoms in ccp structure are 12 at edge centred and 1 at body centre. therefore,
No. of B atoms per unit cell = `12 xx 1/4 + 1 = 4`
`:.` Stoichiometry of compound = `A_3B_4`.