Acidified potassium permanganate solution is decolourised by

When $SO_2$ is bubbled into an acidic $KMnO_4$ solution,decolorization of the purple solution takes place along with the formation of a manganese compound $X$. Under neutral conditions,compound $X$ reacts with $KMnO_4$ in the presence of zinc oxide to give another manganese compound $Y$. The oxidation states of manganese in compounds $X$ and $Y$,respectively,are

The gaseous product of the reaction between $Sn$ and conc. $H_2SO_4$ is

$H_2S$ ($5$ moles) reacts completely with acidified aqueous potassium permanganate solution. In this reaction,the number of moles of water produced is $x$,and the number of moles of electrons involved is $y$. The value of $(x+y)$ is. . . . . .

$200 \ mL$ of $x \times 10^{-3} \ M$ potassium dichromate $(K_2Cr_2O_7)$ is required to oxidise $750 \ mL$ of $0.6 \ M$ Mohr's salt $(FeSO_4 \cdot (NH_4)_2SO_4 \cdot 6H_2O)$ solution in acidic medium. Here $x =$ ?

Ferrous and ferric ions in solution may be distinguished by using