Chemistrymedium · Past Paper
What happens when CO2 is passed through lime water for a long period?
AThe milkiness disappears
BThe milkiness becomes darker
CA blue color appears
DThe solution turns yellow
✓ Correct Answer: A — The milkiness disappears
Excess CO2 reacts with the calcium carbonate precipitate to form soluble calcium bicarbonate, making the solution clear again.
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