Question

The atoms of element 'Y' form hexagonal close packing and the atoms of element X occupies 2/3 portion of the number of tetrahedral voids. Write the formula of the compound formed by X and Y.

• A. $X_{2}Y$
• B. $X_2{Y}_3$
• C. $X_3{Y}_4$
• D. $X_4{Y}_3$

Answer 1

Answer: (D)

$X_4{Y}_3$

Let the number of Y atoms in hexagonal close packing be $x.$

Number of tetrahedral voids $=2x$

Number of X atoms $=\frac{2}{3}\times 2x=\frac{4}{3}x$

Ratio of X and Y$=\frac{4x}{3}:x=4:3$

$\therefore$ Formula of the compound is $X_4{Y}_3$.

Hence, the correct option is $\text{D}$