Question

what happen when a mixture of iron filling and sulphur powder is heated

Answer 1

When fe is heated with S then it uses the property of chemical reaction and it forms feS

Answer 2

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When iron filings and sulphur powderare mixed, both retain their properties. It means they have not undergone any chemical reaction. When this mixtureis heated, they undergo chemical reaction and form ferrous sulphide (FeS). This compound cannot be separated using a magnet.
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