Same chapter3 marksDifficulty: Medium
Describe the fountain experiment with hydrogen chloride and state what it demonstrates.
Study of Compounds: Hydrogen Chloride
3 marksDifficulty: Medium
What is aqua regia? State its composition and one use.
Original Khojo Papers practice question — not from a past board paper.
Answer
Aqua regia is a mixture of one part concentrated nitric acid and three parts concentrated hydrochloric acid by volume. It dissolves noble metals such as gold and platinum, which neither acid attacks on its own, and is used in purifying them.
No citable source has been recorded for this record. Treat it as practice material, not as fact.
Explanation
It works because the nascent chlorine it liberates converts the metal into a soluble chloride.
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