Question

Which one of the following statements is correct when $S{O}_2$ is passed through acidified $K_{2}C{r}_2{O}_7$ solution?

• A. $S{O}_2$ is reduced.
• B. Green $C{r}_2(S{O}_4{)}_3$ is formed.
• C. The solution turns blue.
• D. The solution is decolourised.

Answer 1

The correct option is B Green $C{r}_2(S{O}_4{)}_3$ is formed.

$K_{2}C{r}_2{O}_7+S{O}_2\to K_{2}S{O}_4+C{r}_2(S{O}_4{)}_3+H_{2}O(Green)$