Question

Silvery grey iron filings are added to yellow sulphur powder in a test tube. The contents of the test tube were strongly heated until they glow red. On cooling, it forms a grey dull solid. Which statement is correct about the contents of the test tube in the experiment?

• A. At the end a compound is formed
• B. At start, they cannot be separated with a magnet
• C. At the end, they can be separated with a magnet
• D. At start, there is a compound

Answer 1

Answer: (A)

Correct option: (B)

• A compound results from a chemical reaction between components, forming a new substance.
• When sulphur and iron filings are mixed and heated, form a black colour compound $FeS$ (ferrous sulphide).
• The chemical reaction can be represented as:
• $Fe+S⟶FeS$

Separation by magnet:

Initially, the iron and sulphur can be separated by the magnet because the iron pieces are attracted by the magnet while sulphur does not attract by a magnet.