The number of moles of oxalate ions $(C_2O_4^{2-})$ oxidized by one mole of permanganate ions $(MnO_4^-)$ in acidic medium is

Find the values of $x$ and $y$ for the following balanced equation:
$5H_2O_2 + xClO_2 + 2OH^- \to xCl^- + yO_2 + 6H_2O$

$A_2O_x$ is oxidised to $AO_3^-$ by $MnO_4^-$ in acidic medium. If $1.5 \times 10^{-3} \text{ mole of } A_2O_x$ requires $40 \text{ mL}$ of $0.03 \text{ M } KMnO_4$ solution in acidic medium,which of the following statement$(s)$ is/are correct?

In the equation $H_2S + 2HNO_3 \to 2H_2O + 2NO_2 + S$,the equivalent weight of hydrogen sulphide is:

Assign $A, B, C, D$ from the given type of reaction for the following chemical equation:
$N_2 + 3H_2 \longrightarrow 2NH_3$

Which of the following is a redox reaction?