Question

Identify true statements regarding $H_{2}S$.

• A. $H_{2}S$ can act as both oxidant and reductant.
• B. $H_{2}S$ is a dibasic acid.
• C. Bond angle in $H_{2}S$ is less than ${109.5}^{\circ }$
• D. $H_{2}S$ is a colourless odourless gas.

Answer 1

Answer: (B), (C)

The correct options are
B $H_{2}S$ is a dibasic acid.
C Bond angle in $H_{2}S$ is less than ${109.5}^{\circ }$

-In $H_{2}S$, oxidation state of sulphur is -2, which is minimum for Sulphur so it can only increase its oxidation state and hence act only as reducing agent. Hence (a) is false.

-In, aqueous solution, $H_{2}S$ deassociates as follows.

$H_{2}S$ $\rightleftarrows$ $H^{+}$ $+$ $H{S}^{-}$ $\rightleftharpoons$ ${2H}^{+}$ $+$ $S^{2-}$

Since it can denote ${2H}^{+}$ , it is dibasic acid , Hence(b) is true.

-$H_2$ has two ione pair of electron which repel each other.Hence bond angle of $H_{2}S$ is less than $109.5$$°$, Hence (c) is correct.

-$H_{2}S$ smells like rotten eggs. .Hence (d) is incorrct