with the help of an experiment prove that light in CO2 is necessary for photosynthesis explain
Solution
For proving the necessity of carbon dioxide for photosynthesis, the following steps are performed:
1) A potted plant is taken and placed in complete darkness for 24 to 72 hours to destarch it.
2) Take potassium hydroxide in a conical flask stoppered with a rubber cork. Insert one leaf (still attached to the parent plant) through a hole in the rubber cork. Potassium hydroxide absorbs all the left-over carbon dioxide from the flask.
3) The entire arrangement is exposed to sunlight for 6 hours.
4) The leaf placed in the conical flask with potassium hydroxide solution is tested with iodine solution. This does not turn blue-black.
Inference: The leaf trapped inside the conical flask did not perform photosynthesis as it did not receive any carbon dioxide. This is the reason why it did not answer a positive test for starch.
For proving the necessity of carbon dioxide for photosynthesis, the following steps are performed:
1) A potted plant is taken and placed in complete darkness for 24 to 72 hours to destarch it.
2) Take potassium hydroxide in a conical flask stoppered with a rubber cork. Insert one leaf (still attached to the parent plant) through a hole in the rubber cork. Potassium hydroxide absorbs all the left-over carbon dioxide from the flask.
3) The entire arrangement is exposed to sunlight for 6 hours.
4) The leaf placed in the conical flask with potassium hydroxide solution is tested with iodine solution. This does not turn blue-black.
Inference: The leaf trapped inside the conical flask did not perform photosynthesis as it did not receive any carbon dioxide. This is the reason why it did not answer a positive test for starch.