What is the colour of $FeSO_{4} \cdot 7H_{2}O$ crystals? How does this colour change upon heating? Give the balanced chemical equation for the change.

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(N/A) $FeSO_{4} \cdot 7H_{2}O$ crystals are green in colour. Upon heating,they first lose their water of crystallisation and turn white (anhydrous $FeSO_{4}$). On further heating,they decompose to form ferric oxide $(Fe_{2}O_{3})$,which is reddish-brown in colour,along with sulphur dioxide $(SO_{2})$ and sulphur trioxide $(SO_{3})$ gases.
Step $1$: Loss of water of crystallisation:
$FeSO_{4} \cdot 7H_{2}O(s) \xrightarrow{\Delta} FeSO_{4}(s) + 7H_{2}O(g)$
(Green) (White)
Step $2$: Decomposition of anhydrous ferrous sulphate:
$2FeSO_{4}(s) \xrightarrow{\Delta} Fe_{2}O_{3}(s) + SO_{2}(g) + SO_{3}(g)$
(Reddish-brown)

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