Why a candle blows off when moving air acts on it even if it is getting more oxygen from the wind?
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Solution
Burning of a candle:
When a candle is lit, the heat of the flame vaporizes the liquid wax. The vaporized gases break down the hydrocarbons into molecules of hydrogen and carbon. These molecules are drawn to the flame where they react with oxygen to produce heat, light, water vapor, and carbon dioxide.
The flame of the candle remains stable at an optimum temperature that is high enough to vaporize wax. Also, provide activation energy for wax molecules.
Explanation:
When a candle is lit conventional flow of air is necessary. As air provides sufficient oxygen to generate heat and flame from a candle.
When we blow the air at a higher speed, it moves faster than the speed of the flame front and the flame is carried away from the melted wax.
Also, the fast blowing air creates a cooling effect, reducing the temperature at which hydrogen and carbon molecules present in wax vapor can't react with oxygen. Hence the candle blows off when moving air acts on it.