Question

A small quantity of light green coloured substance is heated in the beginning it loses some water and then suffocating gas is evolved and a red residue is left behind. Answer the following Name the red residue and write its formula Name the suffocating gas and write its formula Name the light green coloured substance and formula What type of reaction

Answer 1

Name the red residue and write its formula:
Name: iron(III) oxide 

Formula: Fe2O3 


Name the suffocating gas and write its formula:
Name: sulfur dioxide and fumes of sulfur trioxide


Formula: SO2 and SO3


 Name the light green coloured substance and formula:


Name: iron(II) sulfate


Formula: FeSO4


Type of reaction: Decomposition

Note:
The equation can be written as:

2 FeSO4 → Fe2O3 + SO2 + SO3

Answer 2

The red residue is Ferric oxide or Iron oxide(III) oxide.

The formula of ferric oxide is Fe₂O₃.

The suffocating gas evolved is Sulphur dioxide and some fumes of Sulphur trioxide.

The formula of Sulphur dioxide is SO₂.

The light green coloured substance is Ferrous Sulphate  or Iron(II) sulphate.

Formula is FeSO₄.

The reaction involved is known as displacement reaction.

2FeSO₄(s) → Fe₂O₃(s) + SO₂(g) + SO₃(g)