The crystal lattice of the compound `M_(x)O_(y)` has cubic close-packed array of oxygen atom with M atoms occupying two-thirds of the octahedral voids. Determine the values of x and y.

Explanation

The crystal lattice of the compound `M_(x)O_(y)` has cubic close-packed array of oxygen atom.
Thus, number of O atoms per unit cell is 4.
M atoms are occupied two-third of the octahedral voids.
Thus, the number of M atoms present per unit cell
`=4xx2/3=8/3`
Therefore, the ratio of M and O atoms per unit cell
`=8/3:4=2:3`
Therefore, the formula of the compound will be `M_(2)O_(3)`.
Thus, x = 2 and y = 3.