JEE Advanced 2023 — Paper 2 — Question 32

For $\mathrm{Br_3O_8}$: All $\mathrm{Br}$ atoms are in positive oxidation state. Thus, zero oxidation atoms $= 0$

For $\mathrm{F_2O}$: $\mathrm{F} = -1$, $\mathrm{O} = +2$

Thus, zero oxidation atoms $= 0$

For $\mathrm{H_2S_4O_6}$: Two central $\mathrm{S}$ atoms are bonded only to $\mathrm{S}$. Thus, zero oxidation atoms $= 2$

For $\mathrm{H_2S_5O_6}$: Three central $\mathrm{S}$ atoms form $\mathrm{S-S}$ chain. Thus, zero oxidation atoms $= 3$

For $\mathrm{C_3O_2}$: Middle carbon is bonded only to carbon. Thus, zero oxidation atoms $= 1$.

Total $= 0 + 0 + 2 + 3 + 1 = 6$