Chemistry - Complete Pblock- Question with Solution | TestHub

More the oxidation state of the central atom (metal) more is its acidity. Hence ${\mathrm{SeO}}_2(\mathrm{O}.\mathrm{S}.$ of $\mathrm{Se}=+4)$ is acidic. Further for a given O.S., the basic character of the oxides increases with the increasing size of the central atom. Thus ${\mathrm{Al}}_2{\mathrm{O}}_3$ and ${\mathrm{Sb}}_2{\mathrm{O}}_3$ are amphoteric and ${\mathrm{Bi}}_2{\mathrm{O}}_3$ is basic.