Question

A compound is made up of two elements M and N. The element N forms ccp and atoms of M occupy (\frac { 1 }{ 3 })rd of tetrahedral voids. What is the formula of compound?

Answer 1

Let the atoms N in cep = x
No of tetrahedral voids = 2x
As (\frac { 1 }{ 3 }) rd of the tetrahedral voids are occupied by atoms M,
Hence, no. of atoms of M = (\frac { 2x }{ 3 })
Ratio of M:N = 20 : (\frac { 2x }{ 3 }) = 2:3
Hence formula of compound is M2 N3