Question

A compound formed by elements `X` and `Y` crystallises in a cubic structure in which the `X` atoms are at the corners of a cube and the `Y` atoms are at the face centres.The formula of the compound is
A. `XY_(3)`
B. `X_(3)Y`
C. `XY`
D. `XY_(2)`

Answer 1

Correct Answer - 1
Exclusively contribution `X` atoms per unit cell
`=8xx(1)/(8)=1`
Exclusive contribution of `Y` atoms per unit cell `=6xx(1)/(2)=3`
Simplest whole number ratio of atoms is `1:3` Hence the empirical formule is `XY_(3)`.