Question

Observe the experimental set up shown aside and answer the questions that follows: why is hydrilla plant used for this experiment?

Answer 1

INTRODUCTION:The end products of photosynthesis are Oxygen(O2),water and starch.So one of the end products is oxygen ,which is proved by this experiment.

AIM:To prove oxygen is evovled during photosynthesis in the presence of sunlight.

APPARATUS:Beaker,water,test tube,hydrilla plant twigs,funnel and sunlight

PRECAUTION:-Setup should be kept in sunlight
-The level of water in the beaker should be over the level of stem of the inverted funnel
-While removing testtube ,place your thumb near mouth of testtube to prevent escape of gas(oxygen) evolved and remove gently.

PROCEDURE:1)Place hydrilla plant twigs in a short stemmed funnel and keep it in a beaker containing water.
2)Invert a test tube full of water over the stem of the funnel
3)Place the apparatus in the sun for at least 2-3 hours.
4)After sometime observe the apparatus

OBSERVATION:1)Gas bubbles i,e.,oxygen is produced at the end of test tube and remove the test tube gently.
2)Test the gas in the testtube by inserting a glowing incense stick which would burst into flames.
3)This shows the presence of oxygen.

RESULT:By this experiment, we proved that oxygen is produced during photosynthesis in the presence of sunlight.