$ + 3{H_2}O + 5O$
$5{H_2}{O_2} + 5O\xrightarrow{{}}5{H_2}O + 5{O_2}$
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$2KMn{O_4} + 3{H_2}S{O_4} + 5{H_2}{O_2}\xrightarrow{{}}{K_2}S{O_4} + 2MnS{O_4}$
$ + 8{H_2}O + 5{O_2}$