InterviewSolution
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InterviewSolution
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Observing what happens in different zones of candle flame.Light a candle. Hold a glass tube (with 7 cm length) a pair of tongs and introduce its one end in the dark zone of a non flickering candle flame. Keep lighted match stick near the other end of the glass tube as shown in the figure. a) What do you observe? Do you see a flame? If so what is it, that produces a flame?b) Notice that the wax near the heated wick melts quickly. What do you observe?c) What is it?d) Hold a thin long copper wire just inside the flame for about half a minute. What do you observe? What is your inference? |
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Answer» a) Yes, the some of vapours produced by wax pass through the glass tube and are burnt by match stick to produce flame. b) When the candle’s flame is steady introduce a clean glass slide into the luminous zone of the flame and hold it with a pair of tongs for 10 seconds. A blackish circular ring is formed on the glass slide. c) The deposition of unburnt carbon particles present in the luminous zone of the flame due to incomplete combustion. d) The copper wire just outside the flame gets red hot. It indicates that the non luminous zone of the flame has high temperature. It is the hottest part of the flame. It is blue in colour and complete combustion takes place due to good supply of oxygen. |
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