JEE Main 2020 — Solid State Question with Solution

O^–2 ions form ccp $$\Rightarrow$$ O₄.

M₁ = 50% octahedral void = $$\frac{50}{100}\times 4$$ = 2

M₂ = 12.5% tetrahedral void = $$\frac{12.5}{100}\times 8$$ = 1

So formula is : (M₁)₂(M₂)₁O₄

Let charge on M₁ and M₂ are +x and +y respectively. And O₄ has -8 charge.

As crystal is neutral. So metals must have +8 charge in total.

$$\therefore$$ +2x + y = 8 ....(1)

By checking options we found eq (1) satisfy when
x = +2
y = +4