Question

(a) Write one reaction in which aluminium oxide behaves as a basic oxide and another in which it behaves as an acidic oxide.
(b) What special name is given to substances like aluminium oxide?
(c) Name another metal oxide which behaves like aluminium oxide.

Answer 1

(a) When aluminium oxide reacts with hydrochloric acid, it behaves as a basic oxide:

$A{l}_2{O}_3\left(s\right)+6HCl\left(aq\right)⟶2AlC{l}_3\left(aq\right)+3H_{2}O\left(l\right)$

When aluminium oxide reacts with a base like sodium hydroxide, it behaves as an acidic oxide:

$A{l}_2{O}_3\left(s\right)+2NaOH\left(aq\right)⟶2NaAl{O}_2\left(aq\right)+H_{2}O\left(l\right)$

(b) Aluminium oxide reacts with both acids and bases and so it is called an amphoteric oxide.

(c) Zinc oxide is another metal oxide that behaves like aluminium oxide.