Same chapter3 marksDifficulty: Medium
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Study of Acids, Bases and Salts
3 marksDifficulty: Medium
Why is concentrated sulphuric acid not used in place of dilute hydrochloric acid to prepare hydrogen sulphide from iron(II) sulphide?
Original Khojo Papers practice question — not from a past board paper.
Answer
Concentrated sulphuric acid is a strong oxidising agent and would oxidise the hydrogen sulphide as fast as it was formed, depositing sulphur instead of setting the gas free. Dilute hydrochloric acid or dilute sulphuric acid simply displaces the gas without oxidising it.
No citable source has been recorded for this record. Treat it as practice material, not as fact.
Explanation
Concentrated nitric acid is ruled out for the same reason.
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