Hydrilla plant experiment

Experiment to demonstrate that oxygen is evolved during the process of photosynthesis:

Answer
Requirements:Beaker, water, test tube, funnel, Hydrilla plant.

Method:

1. Fill the beaker with the water and take an aquatic plant, such as Hydrilla, in the beaker.

2. Cut the bases of the plants, tie them with a thread and cover them with an inverted funnel in such a fashion that the cut ends of plants are towards the neck of the funnel. 

3. Fill a test tube with the water and invert it on the upper end of the funnel.

4. Keep the whole apparatus in sunlight and observe for some time.

Observations:

From the cut ends of the plant some bubbles are coming out continuously and they are collected at the top of the test tube by displacing the water. 

Test for the gas:

To test the gas released, bring a burning match stick near the mouth of the test tube which would burst into flames. This shows that the gas released is oxygen. 

Results:

The liberated gas is oxygen and it is evolved due to the photolysis of water under the process of photosynthesis. 

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