Same chapter3 marksDifficulty: Medium
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Why does hydrogen chloride gas not conduct electricity, while its aqueous solution does?
Original Khojo Papers practice question — not from a past board paper.
Answer
Hydrogen chloride is a covalent compound and in the gaseous state it exists as neutral molecules, with no free ions to carry a current. When it dissolves in water the polar water molecules break the H–Cl bond, giving hydrogen ions and chloride ions, and those free ions carry the current.
No citable source has been recorded for this record. Treat it as practice material, not as fact.
Explanation
This is why hydrochloric acid, but not dry hydrogen chloride gas, turns moist blue litmus red.
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