In the titration of $KMnO_{4}$ and oxalic acid in acidic medium,the change in oxidation number of carbon at the end point is

Consider the following reaction occurring in basic medium $2MnO_4^- (aq) + Br^- (aq) \to 2MnO_2 (s) + BrO_3^- (aq)$. How can the above reaction be balanced further?

What is the number of moles of electrons gained by one mole of oxidizing agent in the following redox reaction?
$Zn_{(s)} + 2HCl_{(aq)} \longrightarrow ZnCl_2(aq) + H_2(g)$

Which of the following solutions will turn violet when a drop of lime juice is added to it?

Assign $A$,$B$,$C$,$D$ from the given type of reaction.
$S + HNO_3 \, (Dil.) \longrightarrow H_2SO_4 + NO \uparrow $

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 $.......$.