Question

The following experiments was set up to show that a gas is given out during respiration. But there was no rise in the level of water. why did it happen

Answer 1

Water level rises up in the bent tube.

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.