In alkaline medium,the reduction of permanganate anion involves a gain of $........$ electrons.

How many moles of $K_2Cr_2O_7$ will be reduced by $1$ mole of $Sn^{2+}$ ions?

After balancing the reaction $Cu + HNO_3 \rightarrow Cu(NO_3)_2 + NO_2 + H_2O$ in an acidic medium,the number of nitrogen atoms,the number of water molecules,and the net charge on the product side are respectively:

The reaction,$K_2Cr_2O_7 + m \, FeSO_4 + n \, H_2SO_4 \longrightarrow Cr_2(SO_4)_3 + p \, Fe_2(SO_4)_3 + K_2SO_4 + q \, H_2O$ when balanced,$m, n, p$ and $q$ are,respectively:

How many grams of $Mg$ is required to completely reduce $100 \ mL$ of $0.1 \ M$ $NO_3^{-}$ solution using the following reaction:
$NO_3^{-} + Mg \longrightarrow Mg^{2+} + NH_3$

Consider the following reaction:
$xMnO_4^{-} + yC_2O_4^{2-} + zH^{+} \rightarrow xMn^{2+} + 2yCO_2 + \frac{z}{2}H_2O$
The values of $x, y$ and $z$ in the reaction are,respectively: