Preistley's bell jar experiment


Write the experiment of the bell jar and pudina plant, performed by Priestly to prove that air plays a key role in photosynthesis

ANSWER

Priestley performed the experiment to prove that the plants are responsible for the recycling of the gas present in the air which is used during burning and respiration. The experiments which were performed are as follows:
1) There was a bell-shaped jar placed upon a burning candle and a live mouse.
2) When the mouse and the candle were placed under the bell jar, the mouse used all the oxygen from the air. This resulted in the extinguishing of the candle due to the absence of oxygen in the air.  The mouse also dies after some time due to the absence of oxygen. 
3) Then a mint plant was placed in the bell jar along with a live mouse and the burning candle. 
4) The plant help in recycling the oxygen in the air by using carbon dioxide. This causes the replenishing of the oxygen in the air which is lost by the respiration by mouse and the burning of the candle.
Thus, the plant can perform photosynthesis and replenish the oxygen in the air which is used by the animals for breathing. 

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