Question

In the bell jar experiment, the air passing through the lime water turned it milky. What is the inference from this observation?

• A. The air drawn in by the pump has carbon dioxide which turns lime water milky.
• B. The air drawn in by the pump has oxygen which turns lime water milky.
• C. The air drawn in by the pump has hydrogen which turns lime water milky.
• D. The air drawn in by the pump has water vapour which turns lime water milky.

Answer 1

The correct option is A

The air drawn in by the pump has carbon dioxide which turns lime water milky.

Plants use oxygen for cellular respiration and give out carbon dioxide. This carbon dioxide reacts with the calcium hydroxide in lime water and produces calcium carbonate which is milky white in appearance.