$C +$ Conc. $H_2SO_4 \xrightarrow{\Delta} X + Y + H_2O$. $X$ and $Y$ in the above reaction are:

In neutral or faintly alkaline solution,$8$ moles of permanganate anion quantitatively oxidize thiosulphate anions to produce $X$ moles of a sulphur containing product. The magnitude of $X$ is

In the reaction $I_2 + 2S_2O_3^{2-} \to 2I^{-} + S_4O_6^{2-}$,the equivalent weight of iodine will be equal to

Observe the following reaction:
$xS_{8\text{(s)}} + yOH^{-}{_{\text{(aq)}}} \rightarrow zS^{2-}{_{\text{(aq)}}} + 2S_2O_3^{2-}{_{\text{(aq)}}} + 6H_2O_{\text{(l)}}$
Find the values of $x, y$ and $z$ respectively.

Number of moles of $MnO_4^-$ required to oxidize one mole of ferrous oxalate completely in acidic medium will be .......... $moles$.

Explain why the colour of $KMnO_4$ disappears when oxalic acid is added to its solution in acidic medium.