Difference in the evolution of gas when sunlight falls directly and indirectly
Answers
Answer:
Photosynthesis is an anabolic chemical process of green plants and it is a food synthesizing process. In this resource I have explained in detail how an experiment can be conducted to prove oxygen is evolved during photosynthesis process. Along with the experiment I gave some important questions as well as answers related to the experiment which will be useful for those preparing for final practical or theory exams of various Boards.
Introduction
Photosynthesis is a physiological process of green plants to manufacture their carbohydrate food. It is a complex chemical process occur in the chloroplasts of mesophyll tissue of green plants. During photosynthesis process green plants utilizes energy from solar radiation, Co2 from atmosphere, water and minerals from obtained from soil to prepare their carbohydrate food and in turn evolve oxygen.
Aim of the experiment:-
To prove that oxygen is evolved in green plants during photosynthesis.
Requirements:-
Hydrilla twigs, Beaker, a glass funnel, a Test tube, a beehive arrangement, pond water, a glowing splinter.
Procedure for the experiment
Take a beaker and fill 3/4ths of it with pond water. Take some freshly cut Hydrilla twigs and insert them in the nozzle from below the stem of a glass funnel. Keep this funnel in an inverted position at the bottom of the beaker. A beehive arrangement is used in between the base of the funnel and bottom of the beaker. Now a test tube is filled with pond water and is inverted over the stem of the funnel. While making this arrangement one has to see the level of water in the beaker should be above the level of stem of the inverted funnel. The whole arrangement is kept on a flat surface under bright sunlight for some time.
Oxygen is evolved by green plants during photosynthesis
Oxygen is evolved by green plants during Photosynthesis (Courtesy:-www.weekispaces.com)
Result of the experiment
Air bubbles start moving from the cut end of the Hydrilla twigs and get collected at the upper end of the test tube. After some time we find some gas get collected at the top of the inverted test tube by downward displacement of water. To test the nature of the gas collected, the test tube is removed quickly from the stem of the funnel and the mouth is closed with the thumb. Now a glowing splinter is introduced into the test tube by removing the thumb from the mouth of the test tube. The glowing splinter immediately burst into a flame indicating that the gas collected in the test tube is oxygen.
