Why Zinc and aluminium are considered to have unique nature. Give balanced equations to support your answer.

Explanation

Zinc and aluminium are considered to have a unique nature because,
(i) They can react with acids and hot concentrated alkalis to form hydrogen and a soluble salt.
`Zn+2NaOH to underset"Sod. Zincate"(Na_2ZnO_2) + H_2`
`underset"(fused)"(2Al) + 6NaOH to underset"Sod. Aluminate"(2Na_2AlO_3) + 3H_2`
(ii) As zinc and aluminium are amphoteric, their oxides react with both bases and acids to give salt and water.
`ZnO + 2HCl to ZnCl_2 + H_2O`
`ZnO+2NaOH to Na_2ZnO_2 + H_2O`