A compound is formed by two elements, M and N. N forms ccp & atoms of M occupy `1/3`rd of tetrahedral voids. What is the formula of the compound?

Explanation

Suppose, number of N-atoms in the ccp structure = x
Number of tetrahedral voids in the ccp structure = 2 `xx` Number of packed atoms i.e., N-atom = 2x `1/3`rd of 2x tetrahedral voids are occupied by M atoms.
Therefore, number of M atom in close-packed structure = `(2x)/3`. Hence, ratio of the number of M and N-atom in the unit cell of the crystal lattice = `(2x)/3:x=2:3`
Therefore, the formula of the compound is `M_(2)N_(3)`.