A student strongly heats hydrated ferrous sulphate salt in a dry test-tube. He would observe a :
(1) yellow residue | (2)brown residue |
(3)light green residue | (4) white residue |
"
Correct answer: (2) brown residue
Explanation: Ferrous sulphate is a hydrated salt that has blue-green colour. On heating in a dry test tube, it will lose its water molecules and become anhydrous Fe2O3 which is reddish-brown in colour.
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