Photosynthesis-Test tube and Funnel Experiment (Demonstration)

PHOTOSYNTHESIS-TEST TUBE AND FUNNEL EXPERIMENT(DEMONSTRATION)

Aim:

To prove that oxygen is evolved during photosynthesis.

Materials required:

Test tube, funnel, beaker, pond water and Hydrilla plant.

Procedure:

1.              Take a few twigs of Hydrilla plant in a beaker containing pond water.

2.              Place an inverted funnel over the plant.

3.              Invert a test tube filled with water over the stem of the funnel.

4.              Keep the apparatus in the sunlight for few hours.

Observation:

After one hour, it is noted that water gets displaced down from the test tube.

Inference

During photosynthesis, oxygen is evolved as a by-product. Gas bubbles liberated from the Hydrilla plant reach the top of the test tube and it displaces the water downwards. Take the test tube and keep the burning stick near the mouth of the test tube. Increased flame will appear. Hence, it is proved that oxygen is evolved during photosynthesis.