Assertion (A): When ferrous sulphate crystals are heated, they first lose water and then decompose to give fe…

Question

Assertion (A): When ferrous sulphate crystals are heated, they first lose water and then decompose to give ferric oxide, sulphur dioxide and sulphur trioxide.
Reason (R): Ferrous sulphate crystals contain water of crystallisation, and heating provides energy to break the compound into simpler substances.
(A) Both A and R are true and R is the correct explanation of A.
(B) Both A and R are true but R is not the correct explanation of A.
(C) A is true but R is false.
(D) A is false but R is true.

Accepted Answer

## Model Answer **(A) Both A and R are true and R is the correct explanation of A.** FeSO₄·7H₂O crystals first lose water of crystallisation on heating, then thermally decompose to give Fe₂O₃, SO₂ and SO₃. R correctly explains the two-step process described in A. Source: Chapter 1, Section 1.2.2 Decomposition Reaction --- ## Explanation The textbook explicitly states that ferrous sulphate crystals (FeSO₄·7H₂O) **first lose water of crystallisation**, then decompose into Fe₂O₃, SO₂, and SO₃. Both steps are caused by heat — first breaking the hydration, then breaking the compound itself. So R (water of crystallisation + heat providing energy for decomposition) directly and correctly explains A. Option (A) is the right choice.

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