Question

A student conducted an experiment to show CO2 in release during respiration.
A) List 3 precautions that he must take for obtaining correct observations.
B) What's happens to CO2 given out by the germinating seeds while performing the experiment.

Answer 1

Precautions:

1. Keep the conical flask airtight.

2. Fix the shorter end of the glass tube in such a way that it does not touch the seeds.

3. Use freshly prepared KOH solution.

Result:

The rise in the level of water indicates that CO2 is produced by germinating seeds during respiration. Actually, the germinating seeds respire and produce CO2, which is absorbed by KOH solution. This creates a vacuum in the conical flask. The air present in the bent glass tube moves into the conical flask. This pulls the water in the bent tube further up.