In a solid 'AB' having rock salt arrangement ( N a C l structure), 'A' atoms occupy the corners and face center of the cubic unit cell. 'B' atoms occupies all octahedral voids of the unit cell. If all the face-centered atoms along one of the axes are removed, then the resultant stoichiometry of the solid is

Step-by-step solution

There were 6 A atoms on the face-centres removing face-centred atoms along one of the axes means removal of 2 A atoms. Now, number of A atoms per unit cell Number of B atoms per unit cell = 12 × 1 4 ( e d g e c e n t r e d ) + 1 = 4 ( b o d y c e n t r e d ) Hence the resultant stoichiometry is A 3 B 4