In the redox reaction $N_2H_4 + ClO_3^- \to NO + Cl^-$ (in basic medium),how many electrons are added in the reduction half-reaction based on the difference in oxidation states?

Which of the following is a redox reaction?

In acidic medium,potassium dichromate acts as an oxidant according to the equation,$Cr_2O_7^{2-} + 14H^{+} + 6e^- \to 2Cr^{3+} + 7H_2O$. What is the equivalent weight of $K_2Cr_2O_7$? (Molecular weight $= M$)

$2 MnO_{4}^{-} + b C_{2}O_{4}^{2-} + c H^{+} \rightarrow x Mn^{2+} + y CO_{2} + z H_{2}O$
If the above equation is balanced with integer coefficients,the value of $c$ is ...........
(Round off to the Nearest Integer).

Assign $A, B, C, D$ from given type of reaction.
$Na_{(s)} + H_2O_{(l)} \xrightarrow{R.T.} NaOH + H_2 \uparrow $

In alkaline medium,the reaction of hydrogen peroxide with potassium permanganate produces a compound in which the oxidation state of $Mn$ is $....$