Chemistry - Complete Pblock- Question with Solution | TestHub

Among the group-13 elements, $\mathrm{B}, \mathrm{Al}, \mathrm{Ga}, \mathrm{In}$ forms oxide of the type ${\mathrm{E}}_2{\mathrm{O}}_3$ on reaction with oxygen. While $\mathrm{Tl}$ has $+1$ state in its oxide and its oxide has the formula ${\mathrm{Tl}}_2\mathrm{O}$.

The nature of oxides of group-13 elements varies down the group. Boron trioxide is acidic and reacts with basic (metallic) oxides forming metal borates. Aluminium and gallium oxides are amphoteric and those of indium and thallium are basic in their properties. The basic nature increases as we move down the group. Thus out the given oxides, the most alkaline one is ${\mathrm{Tl}}_2\mathrm{O}$.