Question

What happens when $H_{2}S$ gas is passed into aqueous $S{O}_2$?

• A. $H_{2}S$ is converted into a yellow precipitate of sulphur.
• B. $S{O}_2$ is converted into yellow precipitate of sulphur.
• C. A clear solution of $H_{2}S{O}_4$ is formed.
• D. $S{O}_2$ and $H_{2}S$ are converted into yellow precipitate.

Answer 1

The correct option is D $S{O}_2$ and $H_{2}S$ are converted into yellow precipitate.

On passing $H_{2}S$ through an aqueous solution of $S{O}_2$ oxidation of $H_{2}S$ occurs while $S{O}_2$ is reduced to produce elemental sulphur which causes the yellow turbidity.

$2H_{2}S+S{O}_2\left(aq\right)\to 3S+2H_{2}O$