Question

A white solid imparts a violet colour to a Bunsen flame. On being heated with concentrated $H_{2}S{O}_4$, the solid gives violet vapours that turns starch paper blue. The salt may be:

• A. $NaI$
• B. $KI$
• C. $CaB{r}_2$
• D. $Mg{I}_2$

Answer 1

The correct option is B $KI$

Salt is KI and

$5H_{2}S{O}_4+8KI\to 4K_{2}S{O}_4+4I_2+H_{2}S+4H_{2}O$