Question

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

Answer 1

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.