Question

In a cubic packed structure of mixed oxides, the lattice is made up of oxide ions, one fifth of tetrahedral voids are occupied by divalent $\left(X^{2+}\right)$ ions. while one half of the octahedral voids are occupied by trivalent ions $\left(Y^{3+}\right)$, then the formula of the oxide is:

• A. $X{Y}_2{O}_4$
• B. $X_{2}Y{O}_4$
• C. $X_4{Y}_5{O}_{10}$
• D. $X_5{Y}_4{O}_{10}$

Answer 1

The correct option is C $X_4{Y}_5{O}_{10}$

Cubic structure- Oxide ions-lattice.

CCP $\frac{1}{5}$ of tetrahedral voids- $x^{2+}$

$N=4$ $\frac{1}{2}$ of octahedral voids- $y^{3+}$

$O_2-1x-\frac{4}{5}y-\frac{2}{2}=1$ $\frac{x_4}{5}Y{O}_2⟹X_4{Y}_5{O}_{10}$