Al(OH)3 act as base and react with acid HCl to give salt and water. (I) Al(OH)3+3HCl⟶AlCl3+3H2O Al(OH)3 act as acid and reacts with base NaOH to give salt and water. (II) Al(OH)3+2NaOH+6H2Ounderset2NaAl(OH)4+3H2O So, Al(OH)3 is amphoteric in nature.