What ions are in Cr2O3?

In chromium(III) oxide (Cr₂O₃), the ions present are chromium ions (Cr³⁺) and oxide ions (O²⁻). Each chromium ion carries a +3 charge, while each oxide ion carries a -2 charge. The compound is neutral overall, with two chromium ions balancing out the three oxide ions. Thus, the formula reflects a ratio of 2:3 between chromium and oxide ions.