Milkiness of lime water is due to which substance?
Answer and explanation
Correct answer: Calcium carbonate
Lime water is a clear solution of calcium hydroxide. When carbon dioxide is passed through it, calcium carbonate is formed: Ca(OH)₂ + CO₂ → CaCO₃ + H₂O. Calcium carbonate is insoluble in water, so its suspended particles scatter light and produce the milky appearance. Thus option A is correct. Sodium chloride and sodium hydroxide do not cause this observation, and hydrogen is not the precipitate formed.
Frequently asked questions
What is the correct answer to this question?
Calcium carbonate
Why is this the correct answer?
Lime water is a clear solution of calcium hydroxide. When carbon dioxide is passed through it, calcium carbonate is formed: Ca(OH)₂ + CO₂ → CaCO₃ + H₂O. Calcium carbonate is insoluble in water, so its suspended particles scatter light and produce the milky appearance. Thus option A is correct. Sodium chloride and sodium hydroxide do not cause this observation, and hydrogen is not the precipitate formed.
Which subject and chapter does this question cover?
This is a Class 10 Science question. Chapter: Chemical Substances – Nature and Behaviour. Topic: Acids, Bases, and Salts.
