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Carbon and its Compounds — Science STD 10 — Question

CBSE BoardEnglish MediumSTD 10ScienceCarbon and its Compounds3 Marks
Question
What makes the candle flame yellow and luminous?
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Answer

When a candle is lighted, the wax melts, rises up the wick and gets converted into vapours. In a candle, there is no provision for the proper mixing of oxygen (of air) for burning wax vapours. So, the wax vapours bum in an insufficient supply of oxygen (of air) which leads to incomplete combustion of wax. This incomplete combustion of wax produces small unburnt carbon particles. These solid carbon particles rise in the flame, get heated and glow to give out yellowish light. This makes the candle flame yellow and luminous.

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