When $K{O}_2$  is dissolved in water which of the following changes occur

$2K{O}_2+2H_{2}O\to 2KOH+H_2{O}_2+O_2$.In the super oxide ion oxygen is in – 0.5 oxidation state. During convertion into $O_2$ and $H_2{O}_2$ its oxidation state increases from – 0.5 to 0 in the formation of $O_2$ and decreases to – 1 in $H_2{O}_2$ During the formation of $H_2{O}_2$. So it is oxidation. As the solution is basic due to formation of $KOH$ is turns the red litmus to blue which turns to colourless due to bleaching action of $H_2{O}_2$