Same chapter3 marksDifficulty: Medium
The solubility of potassium nitrate at 30 °C is 45 g per 100 g of water. What mass of the salt will saturate 250 g of water at that temperature?
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3 marksDifficulty: Medium
Define efflorescence, deliquescence and hygroscopy, giving one example of each.
Original Khojo Papers practice question — not from a past board paper.
Answer
Efflorescence is the loss of water of crystallisation to the air by a hydrated salt, as with washing soda. Deliquescence is the absorption of so much moisture from the air that the substance dissolves in it, as with calcium chloride. Hygroscopy is the absorption of moisture from the air without dissolving, as with concentrated sulphuric acid.
No citable source has been recorded for this record. Treat it as practice material, not as fact.
Explanation
Deliquescent and hygroscopic substances are used as drying agents.
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