# Oxidation of Hexaaquachrom (II) with air

$$\ce{Cr(H2O)6^3+ -> Cr(H2O)6^2+}$$ using $$\ce{Zn}$$ as a reducing agent.
the colour turning from green to blue and I know that with contact with air the solution becomes green again because the $$\ce{Cr(II)}$$ oxidizes to $$\ce{Cr(III)}$$ but what is the reaction for that?
$$\ce{Cr^2+ + O2 -> Cr2O3}$$
and since $$\ce{Cr2O3}$$ is green it explains the colour we see after $$\ce{Cr(H2O)6^2+}$$ reacts with air.