3 K3AsIIIS3-II + 26 HNVO3 3 K3AsVO4 + 9 H2SVIO4 + 26 NIIO + 4 H2O

This is an oxidation-reduction (redox) reaction:

3 AsIII - 6 e- 3 AsV (oxidation)

9 S-II - 72 e- 9 SVI (oxidation)

26 NV + 78 e- 26 NII (reduction)

Change the oxidation states