The volume concentration of hydrogen peroxide having $6.8 \%$ concentration will be

The oxide that gives $H_2O_2$ on treatment with a dilute acid is

$A$ colourless liquid $A$ contains $H$ and $O$ elements only. It decomposes slowly on exposure to light. It is stabilised by mixing urea to store in the presence of light.
$(i)$ Suggest the possible structure of $A$.
$(ii)$ Write the chemical equation for its decomposition reaction in light.

Electrolysis of $X$ gives $Y$ at anode. Vacuum distillation of $Y$ gives $H_2O_2$. The number of peroxy $(O-O)$ bonds present in $X$ and $Y$ respectively are :

$H_2O_2$ acts as an oxidising agent in

The oxidation state of oxygen in hydrogen peroxide $(H_2O_2)$ is: