Question

A pale green solid substance A in a test tube and heated it over the flame of a burner. A brown colored residue B was formed along with evolution of two gases with the smell of burning sulphur. Identify A B. Write the chemical reaction involved and also the type of reaction.

Answer 1

2FeSO₄→Fe₂O₃ + SO₂ +SO₃
It is a decomposition reaction.
A = FeSO₄
B =Fe₂O₃