Question

The following experimental set-ups were kept in the laboratory to show that ‘CO₂ is given out during respiration’.



After two hours, students observed that water rises in the delivery tube:
(1) only in set up (A)
(2) only in set up (B)
(3) in both (A) and (B)
(4) neither in set up (A) nor in set up (B)

Answer 1

In this experiment, the water will rise only in set up A. In set up A, the flask is made air tight with the help of a cork whereas in set up B, a cotton plug is used. It does not create an air tight condition as a result of which water would not rise in set up B.

Hence, the correct answer is option 1.