Question

prove that aluminium oxide is amphoteric in nature

Answer 1

Aluminim reaction with acid : Aluminum oxide contains oxide ions, and thus reacts with acids in the same way sodium or magnesium oxides do. Aluminum oxide reacts with hot dilute hydrochloric acid to give aluminum chloride solution which is a salt.We know that base of oxide of base reacts with acid to give salt.

Similarly Oxide of aluminium react with base to give salt and water.

Answer 2

We know, The metal oxide which reacts with both the acid and base are called amphoteric oxides.

So we just need to show that whether the Aluminium reacts with acids or not

Al2O3+6HCl----›2AlCl3+3H2O

Al2O3+NaOH----›Na2AlO2+H2

Since Aluminium reacts with both acid and base we can say aluminium oxides are amphoteric in nature