2 CrI + 32 KOH + 13 Cl2 → 2 KIO4 + 26 KCl + 2 K2CrO4 + 16 H2O
This is an oxidation-reduction (redox) reaction:
2 I-I - 16 e- → 2 IVII (oxidation)
26 Cl0 + 26 e- → 26 Cl-I (reduction)
2 CrI - 10 e- → 2 CrVI (oxidation)
CrI is a reducing agent, Cl2 is an oxidizing agent, CrI is a reducing agent.