A compound is formed by two elements Y and Z . The element Z forms ccp and atoms Y occupy 1/3 rd of tetrahedral voids. The formula of the compound is

Explanation

The ccp lattice is formed by the element N. The number of tetrahedrls voids is expected to be twice the number of atoms of N. However, only 1/3rd of these holes are occupied i.e., 2/3 voids are occupied by the atoms of the element M. Thus, the atoms of the elements N and M are present in the ratio. `=1:2//3 or 3:2`.
Therefore, the formula of the compound is `N_(3)M_(2)`.