B2-IIIH6 + 2 NaClVO3 2 NaCl-I + 2 H3BIIIO3

This is an oxidation-reduction (redox) reaction:

2 B-III - 12 e- 2 BIII (oxidation)

2 ClV + 12 e- 2 Cl-I (reduction)

Change the oxidation states