Sunita kept a jar of clear lime water open in her room. After two days, a thin white crust formed on its…
Sunita kept a jar of clear lime water open in her room. After two days, a thin white crust formed on its surface. Which characteristic of living things in the room caused this change?
Growth of airborne microorganisms releasing oxygen
Respiration by living organisms releasing carbon dioxide
Excretion of urea into the surrounding air
Reproduction of microscopic airborne algae
Solution
Living organisms release carbon dioxide gas during respiration, which reacts with clear lime water to form a white precipitate of calcium carbonate.