Question

State the reason for the following: 

(i) Aluminium oxide is called an amphoteric oxide. 

(ii) An iron strip dipped in a blue copper sulphate solution turns the blue solution pale green. 

Answer 1

(i) As it reacts with both acids as well as bases to form salts. 

(ii) Iron being more reactive than copper displaces copper from copper sulphate to form green ferrous sulphate solution.