For the balanced equation $NO_2^- + H_2O \to NO_3^- + 2H^+ + ne^-$,the value of $n$ is .......

$Na_2S_2O_3 + I_2 \to$ Product is

Assign $A$,$B$,$C$,$D$ from the given type of reaction.
$Ca(OH)_2 + SO_2 \longrightarrow CaSO_3 \downarrow + H_2O$

Calculate the equivalent weight of $KMnO_4$ in acidic,basic,and neutral media.

In acidic medium,$K_2Cr_2O_7$ shows oxidising action as represented in the half reaction:
$Cr_2O_7^{2-} + XH^+ + Ye^- \rightarrow 2A + ZH_2O$
$X, Y, Z$ and $A$ are respectively:

Balance the following redox reactions by the ion-electron method:
$(a)$ $MnO_{4(aq)}^- + I_{(aq)}^- \to MnO_{2(s)} + I_{2(s)}$ (in basic solution)
$(b)$ $MnO_{4(aq)}^- + SO_{2(g)} \to Mn_{(aq)}^{2+} + HSO_{4(aq)}^-$ (in acidic solution)
$(c)$ $H_2O_{2(aq)} + Fe_{(aq)}^{2+} \to Fe_{(aq)}^{3+} + H_2O_{(l)}$ (in acidic solution)
$(d)$ $Cr_2O_7^{2-} + SO_{2(g)} \to Cr_{(aq)}^{3+} + SO_{4(aq)}^{2-}$ (in acidic solution)