Question

The lower oxides of transition metals are basic, whereas the highest are amphoteric/acidic. Give reason.

Answer 1

In lower oxidation states, transition metals exhibit metallic characteristics, and their oxides are fundamentally basic. Consequently, transition metal oxides exhibit basicity in lower oxidation states. As oxidation occurs, the metallic character decreases owing to size reduction, making it less metallic or more non-metallic. Non-metal oxides can be either acidic or neutral. Transition metal oxides exhibit amphoteric or acidic properties at higher oxidation states.