2 As2IIIS3-II + 11 HNVO3 + 2 H2O H3As4-3/4 + 6 H2SVIO4 + 11 NIIO

This is an oxidation-reduction (redox) reaction:

4 AsIII + 15 e- 4 As-3/4 (reduction)

6 S-II - 48 e- 6 SVI (oxidation)

11 NV + 33 e- 11 NII (reduction)

Change the oxidation states