Cr2VIIO7 + 4 SIVO2 + 6 H3O+ 2 (CrIII)3+ + 4 SVIO3 + 9 H2O

This is an oxidation-reduction (redox) reaction:

4 SIV - 8 e- 4 SVI (oxidation)

2 CrVII + 8 e- 2 CrIII (reduction)

Change the oxidation states

Warning: Unknown compound 'Cr2O7'