The number of electrons involved in the reduction of permanganate to manganese dioxide in acidic medium is $.......$.

Assign $A, B, C, D$ from the given type of reaction for the following chemical equation:
$Mg_{(s)} + 2HCl_{(aq)} \longrightarrow MgCl_{2(aq)} + H_{2(g)}$

Assign $A, B, C, D$ from the given type of reaction.
$H_3PO_2 + AgNO_3 \longrightarrow Ag + H_3PO_4 + HNO_3$ (Note: The reaction is balanced as $H_3PO_2 + 4AgNO_3 + 2H_2O \longrightarrow 4Ag + H_3PO_4 + 4HNO_3$)

The total change in the oxidation state of manganese involved in the reaction of $KMnO_4$ and potassium iodide in the acidic medium is $..........$.

$H_2O_2$ reduces $MnO_4^-$ ion to:

Assign $A$,$B$,$C$,$D$ from the given type of reaction.
$3PbS \downarrow + 8HNO_3(dil.) \longrightarrow 3Pb(NO_3)_2 + 3S + 2NO \uparrow $