Consider the following molecules : $\mathrm{Br}_{3} \mathrm{O}_{8}, \mathrm{~F}_{2} \mathrm{O}, \mathrm{H}_{2} \mathrm{~S}_{4} \mathrm{O}_{6}, \mathrm{H}_{2} \mathrm{~S}_{5} \mathrm{O}_{6}$, and $\mathrm{C}_{3} \mathrm{O}_{2}$. Count the number of atoms existing in their zero oxidation state in each molecule. Their sum is ____.

JEE Advanced · 2023 · 04 Jun 2023 · Paper 2 · Redox Reactions and Electrochemistry

Consider the following molecules :

Br_{3} O_{8}, F_{2} O, H_{2} S_{4} O_{6}, H_{2} S_{5} O_{6}

, and

C_{3} O_{2}

.
Count the number of atoms existing in their zero oxidation state in each molecule. Their sum is ____.

Answer: 6

Analyzing each molecule for atoms in zero oxidation state:

$H_{2} S_{4} O_{6}$ (tetrathionate): The structure has two terminal S atoms with oxidation state +5 and two central S atoms with oxidation state 0. Count = 2.

$H_{2} S_{5} O_{6}$ (pentathionate): The structure has two terminal S atoms with oxidation state +5 and three central S atoms with oxidation state 0. Count = 3.

$C_{3} O_{2}$ (carbon suboxide): Structure is O=C=C=C=O. The central C atom has oxidation state 0, while the two terminal C atoms have oxidation state +2. Count = 1.

Total sum = 0 + 0 + 2 + 3 + 1 = 6.

JEE Advanced · 2023 · 04 Jun 2023 · Paper 2 · Integer answer