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'A burning candle gets put out after some time of being covered with a glass jar.' Which of the following inference can be drawn from the above observation?  A. Air is required for the burning of candle. B. Oxygen is required for the burning of candles.

'A burning candle gets put out after some time of being covered with a glass jar.' Which of the following inference can be drawn from the above observation?  A. Air is required for the burning of candle. B. Oxygen is required for the burning of candles. Correct Answer Only A

Combustion is a chemical reaction in which a material reacts with oxygen to produce heat and energy.

Key PointsA burning candle gets put out after some time of being covered with a glass tumbler because the oxygen in the air within the glass tumbler is fully consumed to burn the candle. All the oxygen present in the tumbler gets wholly transformed into carbon dioxide. Because carbon dioxide does not support combustion, hence candle will stop burning.

  • Air contains oxygen which helps to encourage combustion. Air is required for the burning of candles as there will be no oxygen if there is no air, the absence of a supporter of combustion will prevent burning.

Confusion Points

  • While introducing this topic student is not already aware of the fact that which of the gas is required to encourage combustion so the student will interpret generalized information i.e air is required for the burning of the candle.

Hence, we conclude that option 1 is correct.

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