The diagram alongside represents an experiment conducted to prove the importance of a factor in photosynthesis.
Study the same and then answer the questions that follow:
Figure

(i) Name the factor being studied in this experiment.
(ii) Why was the plant kept in a dark room before conducting the experiment?
(iii) Why was the experimental leaf then kept in
1. boiling water

2. methylated spirit?
(iv) Name the solution used to test for the presence of starch in the leaf.
(v) What will we observe in the experimental leaf at the end of the starch test?
(vi) Give a balanced chemical equation to represent the process of photosynthesis.

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Solution

(i) The factor that is being studied in this experiment is light.

(ii) The plant is kept in dark before conducting the experiment to destarch it.

(iii) 1. The experimental leaf was kept in boiling water to make it soft.
2. The experimental leaf was kept in methylated spirit to remove cholorophyll and thereby the colour of the leaf.

(iv) Iodine solution is used to test the presence of starch in the leaf.

(v) The area covered with black paper will not turn blue-black on adding iodine solution, while the rest of the area of the leaf will turn blue-black. This shows that light is necessary for photosynthesis to take place.

(vi) 6CO₂ + 12H₂O $\to_{Chlorophyll}^{Sunlight}$ C₆H₁₂O₆ + 6O₂ + 6H₂OloophyllSunl

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