Question

A light green coloured hydrated metallic salt on heating loses water of crystallisation molecule and gives a
suffocating/Pungent odour gas.
(1)
Identify the salt used and gas produced in this reaction.
(1)
Write the name and balanced chemical equation for this reaction.
(iii)
Name the solid product formed in this reaction and also write its colour.
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Answer 1

● Light green coloured hydrated metallic salt on heating loses water of crystallization molecule in this reaction the salt used is ferrous sulfate salt FeSo4.7H2O.

● Two gases are liberated during this reaction Sulphur dioxide and sulphur trioxide.

● The reaction that takes place is

2FeSO₄ → Fe₂O₃ + SO₂ + SO₃

● The solid product formed is ferric oxide Fe2O3. It is Red Brown in colour seems like Rust.

Answer 2

A light green coloured hydrated metallic salt

Explanation:

The light green coloured hydrated metallic salt is green vitriol which on heating loses water of crystallisation molecule and gives a suffocating/ pungent odour gas which is sulphur dioxide.

1. The salt used is Green Vitriol and gas produced in this reaction is sulphur dioxide gas.

2. It is an oxidation reduction reaction.

FeSO4 = Fe2O3 + SO2 + SO3

3. The solid product formed in this reaction is Ferric oxide.

It is reddish brown in colour.