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Question
What is the colour of ferrous sulphate crystals? How does this colour change after heating?
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Solution
The colour of ferrous sulphate crystal is green. After heating, the ferrous sulphate crystal loses water molecules and forms anhydrous ferrous sulphate, which is white in colour. Subsequently, it decomposes to give ferric oxide, which is brown in colour, sulphur dioxide and sulphur trioxide.
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