Assign $A, B, C, D$ from the given type of reaction.
$MnSO_4 + Sr(NO_3)_2 \longrightarrow SrSO_4 \downarrow + Mn(NO_3)_2$

Balance the following equations in basic medium by ion-electron method and oxidation number methods and identify the oxidising agent and the reducing agent.
$(a)$ $P_{4(s)} + OH_{(aq)}^{-} \to PH_{3(g)} + HPO_{2(aq)}^{-}$
$(b)$ $N_{2}H_{4(l)} + ClO_{3(aq)}^{-} \to NO_{(g)} + Cl_{(g)}^{-}$
$(c)$ $Cl_{2}O_{7(g)} + H_{2}O_{2(aq)} \to ClO_{2(aq)}^{-} + O_{2(g)} + H^{+}$

Number of moles of $H^{+}$ ions required by $1 \ mole$ of $MnO_4^{-}$ to oxidise oxalate ion to $CO_2$ is . . . . . .

$KMnO_4$ oxidises hydrogen sulphide in acidic medium. The number of moles of $KMnO_4$ which react with one mole of hydrogen sulphide is

What are $x, y$ and $z$ respectively in the following reaction?
$xFe^{2+}{_{\text{(aq)}}} + yH^{+}{_{\text{(aq)}}} + zCr_2O_7^{2-}{_{\text{(aq)}}} \rightarrow \frac{y}{2}H_2O_{\text{(l)}} + xFe^{3+}{_{\text{(aq)}}} + 2zCr^{3+}{_{\text{(aq)}}}$

For the reaction $Cr_2O_7^{2-} \xrightarrow{H^+} Cr^{3+}$,what is the equivalent weight of $Cr_2O_7^{2-}$?