Question:
On treating a compound with warm dil. $\mathrm{H}_{2} \mathrm{SO}_{4}$, gas $\mathrm{X}$ is evolved which turns $\mathrm{K}_{2} \mathrm{Cr}_{2} \mathrm{O}_{7}$ paper acidified with dil. $\mathrm{H}_{2} \mathrm{SO}_{4}$ to a green compound $\mathrm{Y} . \mathrm{X}$ and $\mathrm{Y}$ respectively are :
Correct Option: 1
Solution:
$\underset{(\mathrm{X})}{\mathrm{SO}_{2}}+\mathrm{K}_{2} \mathrm{Cr}_{2} \mathrm{O}_{7}+\mathrm{H}_{2} \mathrm{SO}_{4} \longrightarrow \underset{(\mathrm{Y})}{\mathrm{Cr}_{2}\left(\mathrm{SO}_{4}\right)_{3}}+\mathrm{K}_{2} \mathrm{SO}_{4}+\mathrm{H}_{2} \mathrm{O}$