2 KMnVIIO4 + 10 KI-I + 8 H2SO4 2 MnIISO4 + 6 K2SO4 + 5 I20 + 8 H2O

This is an oxidation-reduction (redox) reaction:

2 MnVII + 10 e- 2 MnII (reduction)

10 I-I - 10 e- 10 I0 (oxidation)

Change the oxidation states