Question

Name the product formed when ferrous sulphate is heated in the dry test tube. Action is the example of -

Answer 1

Hint: Iron (II) sulphate, also known as ferrous sulphate, is a group of salts with the formula $ FeS{O_4}.x{H_2}O $ . The heptahydrate ( $ x = 7 $ ) is the most common form of these compounds, but they are also classified for other x values. The hydrated form is used to treat iron deficiency in both medical and industrial settings.

Complete answer:
A chemical reaction in which one reactant breaks down into two or more components is known as a decomposition reaction.
A decomposition reaction's general format is shown below.
 $ AB \to A + B $
The parent molecule (reactant) is $ AB $ , and the product molecules are $ A $ and $ B $ .
Iron (II) sulphate loses its water of crystallisation when heated, and the initial green crystals become a white anhydrous solid. The anhydrous material releases sulphur dioxide when heated further, leaving a reddish-brown iron (III) oxide. At about $ 680^\circ C $ , Iron (II) sulphate starts to decompose.
When heated in a dry test tube, it decomposes, that is, it breaks down into two or more components. Sulphur dioxide and sulphur trioxide are formed, as well as a solid ferric oxide that remains as such and is referred to as residue.
The decomposition chemical reaction is as follows:
 $ 2FeS{O_4} \to F{e_2}{O_3}(s) + S{O_2}(g) + S{O_3}(g) $
Observation:
-The crystals of ferrous sulphate are light green in colour.
-The odour of burning sulphur can be detected in the gas released.
-The colour switches from light green to white when heated.
-The white material transforms into a dark brown solid as it is heated further.

Note:
Do not direct the boiling tube's mouth at your neighbours or yourself. When keeping the test tube at a point, gently waft gases released from ferrous sulphate into your nose. Since the gases $ S{O_2} $ and $ S{O_3} $ are extremely dangerous, do not take a deep breath while smelling their odour.