Question

In metal oxide, the oxide ions are arranged in corners as well as on faces and metal cation occupy $\frac{2}{3}$ of octahedral voids, the formula of oxide is:

• A. $M_2{O}_3$
• B. $MO$
• C. $M_{2}O$
• D. $M{O}_1$

Answer 1

The correct option is A $M_2{O}_3$

Oxide ions are involved in forming closed packing structure.

Let, number of oxide ions $=n$

Number of octahedral voids $=n$

So, number of metal ions $=\frac{2}{3}n$

Now, $M^{+}:O^{-}\Rightarrow M^{3+}:O$

$\frac{2}{3}n:n$ $2:3$

So, formula is $M_2{O}_3$