Final answer:
The formula for manganese(III) oxide is Mn₂O₃, which corresponds to option E. It consists of manganese ions with a +3 charge balancing with oxide ions.
Step-by-step explanation:
The formula for manganese(III) oxide is E. Mn₂O₃. This compound consists of manganese in the +3 oxidation state. As manganese can have multiple oxidation states, it is essential to note the Roman numeral (III) in the name, which indicates the +3 state.
For manganese(III) oxide, the presence of two manganese atoms each with a +3 charge balances the -2 charge of three oxide ions, leading to the neutral compound Mn₂O₃.