In the reaction $2Ag + 2H_2SO_4 \to Ag_2SO_4 + 2H_2O + SO_2$,$H_2SO_4$ acts as

Which of the following anions would decolourise acidified $KMnO_4$ solution?

Which of the following groups of molecules act as both an oxidising agent and a reducing agent?

In the reaction $Cr_2O_7^{2-} + X \xrightarrow{H^+} Cr^{3+} + H_2O + \text{Oxidized product of } X$,which of the following cannot be $X$?

Which of the following is the strongest oxidizing agent?

To an acidic solution of an anion,a few drops of $KMnO_4$ solution are added. Which of the following,if present,will not decolourise the $KMnO_4$ solution?