What is the oxidation number of chlorine in hypochlorous acid $(HOCl)$?

$2$ mole of $N_2H_4$ loses $16$ mole of electrons and is converted to a new compound $X$. Assuming that all of the $N$ atoms appear in the new compound,what is the oxidation state of $N$ in $X$?

Write the oxidation number of oxygen in $KO_{3}$ and $Na_{2}O_{2}$.

Write the Lewis structure of the $O_2^-$ ion and find out the oxidation state of each oxygen atom. What is the average oxidation state of oxygen in this ion?

$1 \ mol$ of compound $N_2H_4$ loses $10 \ mol$ of electrons to form a new compound $Y$. Assuming all nitrogen atoms are present in compound $Y$,what is the oxidation state of $N$ in compound $Y$?

Find the oxidation state of sodium in $Na_2O_2$.