Question

Priestley’s bell jar experiment led to the hypothesis that

• A. plants were capable of restoring oxygen which had been completely used up by the mouse and the burning candle
• B. carbon dioxide is essential for photosynthesis
• C. suffocation of the mouse is caused due to the fumes from the burning candle
• D. sunlight is essential for photosynthesis

Answer 1

The correct option is A plants were capable of restoring oxygen which had been completely used up by the mouse and the burning candle

In 1770, Priestley performed the famous bell jar experiment. He placed a burning candle in an air-tight bell jar. He observed that the candle got extinguished in a while. He took the experiment ahead by placing a mouse in the same air-tight jar. He noticed that the mouse suffocated and died in a while. Next, he kept a mint plant along with a mouse and a burning candle in the same bell jar. He demonstrated that the plant kept in the air-tight bell jar produced oxygen using the process of photosynthesis and replenished the air. This ensured the continued survival of the mouse and the burning candle in the jar. In the absence of the plant, the mouse died due to suffocation and the candle got extinguished.
Mohl’s half leaf experiment proved that ${\text{CO}}_2$ is essential for photosynthesis.
Jan Ingenhousz proved that sunlight is essential for photosynthesis.
Option (c) is a wrong inference that could be made from Priestley’s bell jar experiment. Hence, options b, c and d can be eliminated.