Experiment: A burning candle was placed in a closed bell jar.Observation: The flame extinguished after some time and condensation appeared inside the jar.Question: What conclusion can be made?
Correct answer: B. Oxygen is necessary for combustion and is used up.
- A. Carbon dioxide supports combustion.
- B. Oxygen is necessary for combustion and is used up.
- C. Water is released from the wax only due to heat.
- D. Air becomes flammable over time.
Explanation
The correct answer is B: Oxygen is necessary for combustion and is used up. The observation of the flame extinguishing and condensation appearing inside the closed bell jar indicates that oxygen, essential for combustion, was consumed by the burning candle. Option A is incorrect as carbon dioxide does not support combustion. Option C is incorrect as the condensation is not solely due to the release of water from the wax. Option D is incorrect as air does not become flammable over time.
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