Chemistry - Solid State Question with Solution | TestHub

Let the number of atoms of element B in the hcp structure be $N$.

In a close-packed structure, the number of octahedral voids generated is equal to the number of atoms in the packing. Thus, the number of octahedral voids is $N$.

Atoms of element A occupy $\frac{2}{3}$ of the octahedral voids.

Number of atoms of A $=\frac{2}{3}\times N$

The ratio of the number of atoms of A to that of B is:

$\text{A}:\text{B}=\frac{2}{3}N:N=2:3$

The formula of the compound is ${\text{A}}_2{\text{B}}_3$.

Answer: ${\text{A}}_2{\text{B}}_3$