In the given chemical reaction,colors of the $Fe^{2+}$ and $Fe^{3+}$ ions,are respectively :
$5 Fe^{2+} + MnO_{4}^{-} + 8 H^{+} \rightarrow Mn^{2+} + 4 H_{2} O + 5 Fe^{3+}$

How many protons will be consumed when dichromate ion oxidises $Fe^{2+}$ ions in aqueous acidic medium?

The coefficients $x, y, p, q,$ and $r$ in the following balanced equation are respectively:
$xMnO_4^{2-}{_{\text{(aq)}}} + yH_2O_{\text{(l)}} \rightarrow pMnO_2{_{\text{(s)}}} + qMnO_4^{-}{_{\text{(aq)}}} + rOH^{-}{_{\text{(aq)}}}$

Reaction of $Br_2$ with $Na_2CO_3$ in aqueous solution gives sodium bromide and sodium bromate with evolution of $CO_2$ gas. The number of sodium bromide molecules involved in the balanced chemical equation is

The number of moles of $K_2Cr_2O_7$ reduced by $1 \, mol$ of $Sn^{2+}$ is:

See the following chemical reaction:
$Cr_2O_7^{2-} + XH^{+} + 6Fe^{2+} \rightarrow YCr^{3+} + 6Fe^{3+} + ZH_2O$
The sum of $X$,$Y$ and $Z$ is $.......$.