The normality of $10$ $V$ (volume) hydrogen peroxide is:

$H_2O_2$ is

Hydrogen peroxide acts both as an oxidising and as a reducing agent depending upon the nature of the reacting species. In which of the following cases $H_2O_2$ acts as a reducing agent in acidic medium?

The volume of oxygen liberated from $15 \, mL$ of $20$ volume $H_2O_2$ is ................ $mL$.

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

$(i)$ What mass of hydrogen peroxide will be present in $2 \, L$ of a $5 \, M$ solution?
$(ii)$ Calculate the mass of oxygen which will be liberated by the decomposition of $200 \, mL$ of this solution.