Question

When $H_2{O}_2$ is added to ice cold solution of acidified potassium dichromate in ether and the contents are shaken and allowed to stand:

• A. A blue colour is obtained in ether due to formation of $C{r}_2(S{O}_4{)}_3$
• B. A blue colour is obtained in ether due to formation of $Cr{O}_5$
• C. A blue colour is obtained in ether due to formation of $Cr{O}_3$
• D. Chromyl chloride is formed

Answer 1

The correct option is B A blue colour is obtained in ether due to formation of $Cr{O}_5$

When $H_2{O}_2$ is added to ice cold solution of acidified potassium dichromate in ether and the contents are shaken and allowed to stand a blue colored solution is obtained in ether due to formation of $Cr{O}_5$.
$C{r}_2{O}_7^{2-}+2H^{+}+4H_2{O}_2\to \underset{\text{Blue colour in either}}{2Cr{O}_5}+5H_{2}O$