Question

(a) Differentiate between roasting and calcination. Explain the two with the help of suitable chemical equations. How is zinc extracted from its ore? 

(b) Name two metals that can be used to reduce metal oxides to metals.

Answer 1

(a) Roasting: It is a process in which sulphide ore is heated in the presence of oxygen to convert into oxide.

2ZnS + 3O₂ →2ZnO +2SO₂

Calcination: It is a process in which carbonate ore is heated in the absence of air to form oxide.

By reduction process, Zn can be extracted from its ore.

(b) Aluminium, Magnesium