Question

In metal oxide, $O^{2 -}$ ions are arranged in hcp lattice while metal ions occupy $\frac{2}{3}rd$ of octahedral voids. The simplest formula of oxide is

• A. MO
• B. $M_{2}O_{3}$
• C. $MO_{2}$
• D. $M_{2}O$

Answer 1

Answer: (B)

Number of $O^{2 -}$ ions = n

Number of octahedral voids = n

Number of $M^{n +}$ ions $=\frac{2}{3}n$

Ratio of M and $O=\frac{2}{3}n:n$

= 2 : 3

So simplest formula of solid $=M_{2}O_{3}$ .