In neutral or alkaline solution, $$\mathrm{MnO}_{4}^{-}$$ oxidises thiosulphate to :
Given below are two statements.
Statement I : Iron (III) catalyst, acidified $$\mathrm{K}_{2} \mathrm{Cr}_{2} \mathrm{O}_{7}$$ and neutral $$\mathrm{KMnO}_{4}$$ have the ability to oxidise $$\mathrm{I}^{-}$$ to $$\mathrm{I}_{2}$$ independently.
Statement II : Manganate ion is paramagnetic in nature and involves $$\mathrm{p} \pi-\mathrm{p} \pi$$ bonding.
In the light of the above statements, choose the correct answer from the options given below.
The total number of $$\mathrm{Mn}=\mathrm{O}$$ bonds in $$\mathrm{Mn}_{2} \mathrm{O}_{7}$$ is __________.
The dark purple colour of $$\mathrm{KMnO}_{4}$$ disappears in the titration with oxalic acid in acidic medium. The overall change in the oxidation number of manganese in the reaction is :