${H_2}\mathop S\limits^{ } {O_4}\,\,\,\,\, \to \,\,\,\,\,\mathop S\limits^{ } {O_2}$
$CH_4\, _{( g )}+4 Cl _{2}\,_{( g )} \rightarrow CCl _{4}\,_{( l )}+4 HCl\,_ {( g )}$
$xMn{O_4}^ - \, + \,y{H_2}S{O_4}\, \to \,2M{n^{2 + }}\, + \,5{H_2}O\, + \,z{e^ - }$