The product of $I^-$ with $MnO_4^-$ in alkaline medium is

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

In the reaction $Zn + 2H^{+} + 2Cl^{-} \to Zn^{2+} + 2Cl^{-} + H_2$,the spectator ion is

$A$ solution of $Na_2S_2O_3$ is standardized iodometrically against $0.167 \ g$ of $KBrO_3$ where $BrO_3^-$ changes to $Br^-$. This process requires $45 \ mL$ of the $Na_2S_2O_3$ solution. What is the strength of the $Na_2S_2O_3$ in $N$?
$[Mw \text{ of } KBrO_3 = 167]$

$KMnO_4$ oxidises oxalic acid to $CO_2$ in acidic medium. The equivalent weight of $KMnO_4$ is $(Mn = 55, K = 39, O = 16)$:

The equivalent weight of $KIO_3$ in the reaction $2Cr(OH)_3 + 4OH^{-} + KIO_3 \to 2CrO_4^{2-} + 5H_2O + KI$ is