2 g of ferrous sulphate crystals are heated in a dry boiling tube.(a) List any two observations.(b) Name the type of chemical reaction taking place.(c) Write balanced chemical equation for the reaction and name the products formed.

(a) Ferrous sulphate crystals are light green in colour and contain water molecules (FeSO₄. 7H₂O).

• On heating, ferrous sulphate crystals lose water molecules and form white anhydrous ferrous sulphate (FeSO₄).
• On strongly heating, it becomes brown ferric oxide.

(b) This is a type of decomposition reaction (thermal decomposition).

(c) The chemical equation for the reaction is given below:

$FeSO_4.7H_2O (s) \rightarrow FeSO_4 + 7H_2O$

$2FeSO_4 (s) \rightarrow Fe_2O_3(s) + SO_2(g) + SO_3(g) $

The products formed on strongly heating ferrous sulphate crystals are ferric oxide, sulphur dioxide and sulphur trioxide.