Question

In a solid ‘AB' having the NaCl structure, ‘A’ atoms occupy the every CCP and B atoms are in OHV. If all the face-centred atoms along one of the axes are removed, then the resultant stoichiometry of the solid is-
(1) AB2
(2) A2B
(3) A4B3
(4)A3B4​

Answer 1

Answer:

Option 4.

Explanation:

Initially there are 4 A atoms and 4 B atoms .

If all the face centred atoms along one of the axes are removed, 2 face centred atoms will be removed. As the contribution of face centred atom is 1/2 , No. of A atoms removed = 2*1/2 = 1 atom.

Therefore , no. of A atoms = 3 ;B atoms = 4

A3B4 is the formula. OPTION 4

Answer 2

4

Explanation:

an face centered contributes actually 4 atom and one atom is removed from it axes that is 4-1=3

thus

a=3

b=4