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Is there any experiment to show the photosynthesis of plants in our naked eyes?
 Collect leaves from the plants to be tested.

Use forceps to hold the leaf in a beaker of boiling water to kill it

b At your desk, pour some boiling water from a kettle into a large beaker.

c Using forceps, pick up one of your leaves and hold it in the hot water for about one minute.

d Using forceps, remove the leaf from the boiling water and note how it has changed.

e Drop the leaf into a boiling tube and push it to the bottom with a glass rod. Add some anti-bumping granules (optional). Label this tube with your initials if you will be placing it in a hot water bath.
Add enough ethanol to cover the leaf, and stand the boiling tube in your beaker of hot water, or in the hot water bath.

h Watch as the ethanol boils and the green colouring (chlorophyll) is removed from the leaf. This will take a few minutes.

i Replace the hot water with freshly-boiled water from the kettle after 5 minutes if there is still some green colour in the leaf.

j Using forceps, remove the leaf from the boiling tube and rinse the leaf in cold water.
 k Put the leaf in a Petri dish on a white tile.

l Add iodine solution to the leaf from the dropper bottle. Make sure the leaf is completely covered with iodine.

m Watch for a few minutes to see if a blue-black colour develops in any part of the leaf. A blue-black colour with iodine solution indicates that starch is present.

n Wash your hands to remove any traces of plant sap, or the chemicals that you have used.


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