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Question
When a mixture of iron powder and sulphur powder is heated strongly to form iron sulphide, then heat energy is :
Options
released
first absorbed and then released
absorbed
neither absorbed nor released
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Solution
first absorbed then released
When a mixture of iron and sulphur is heated strongly, they first absorb the energy to get excited. This is followed by the formation of a new compound iron sulphide (FeS) with the release of huge amount of energy in the form of heat and light.
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