Chemistry - Solid State Question with Solution | TestHub

$\mathrm{X}$atoms are at eight corners of the cube. Therefore, the number of$\mathrm{X}$atoms in the unit cell$=\frac{8}{8}=1$.
$\mathrm{Y}$atoms are at the face centre of six faces. Therefore, its share in the unit cell$=\frac{6}{2}=3$. The formula is$\mathrm{X}{\mathrm{Y}}_3$.