Classify the following types of reactions:

(i) 2Al + Fe₂O₃ ⟶ Al₂O₃ + 2Fe

(ii) 2KClO₃ ⟶ 2KCl + 3O₂

(iii) BaCl₂ + Na₂SO₄ ⟶ BaSO₄ + 2NaCl

Mohr's salt has the formula (NH₄)₂SO₄.FeSO₄.6H₂O

(i) Calculate its molecular mass.

(ii) What is the percentage of Nitrogen in Mohr's salt ? (Atomic mass: N =14, H = 1, S = 32, Fe = 56, O = 16)

What do you understand by ozone depletion ?

This question relates to the industrial manufacture of Hydrogen.

(i) Name the process.

(ii) Give the main reactions with conditions.