Lowest Oxidation number of an atom in a compound $\mathrm{A}_{2}\mathrm{~B}$ is -2. The number of an electron in its valence shell is

JEE Main · 2024 · 01 Feb 2024 · Shift 1 · Redox Reactions and Electrochemistry

Lowest Oxidation number of an atom in a compound

A_{2} B

is -2. The number of an electron in its valence shell is

Answer: 6

In the compound A

_{2}

B, if the lowest (most negative) oxidation state of the atom "B" is

- 2

, B exists as B

^{2 -}

with a complete octet (8 valence electrons) in its anionic form. Since it gained 2 electrons to complete that octet, the neutral atom B has

8 - 2 = 6

electrons in its valence shell.

JEE Main · 2024 · 01 Feb 2024 · Shift 1 · Integer answer