A flickering flame may cause the heat required for combustion to fluctuate. If you see a wisp of smoke, that's soot carbon from incomplete combustion. Vaporized wax does exist right around the flame but doesn't travel very far or last very long once the candle is extinguished. One interesting project to try is to extinguish a candle and relight it from a distance with another flame. If you hold a lit candle, match or lighter close to a freshly extinguished candle, you can watch the flame travel along the wax vapor trail to relight the candle.
Actively scan device characteristics for identification. Use precise geolocation data. Select personalised content. Create a personalised content profile. Measure ad performance. Select basic ads. Create a personalised ads profile. Select personalised ads. Apply market research to generate audience insights. Does the candle light? Next touch the candle's wick with the flame of the match.
Hold it there for about a second. What happens when you touch the wick with the flame? If the wick did not ignite, light it now. Watch the candle burn for a couple of seconds. Can you describe the flame? How does it look? Blow out the candle and watch what happens. Do you see white smoke escaping from the wick?
Light the candle again then light another match. While the match is still burning blow out the candle. Immediately afterward hold the flame of the match into the white smoke of the blown-out candle, close to the wick but without touching it. What happens? Does the candle light again? Why or why not? Blow out the burning candle. Now stand two candles next to each other in your wet sand or other material so that they are secure and will not fall over.
They should almost touch each other. Light both candles with a match. While both candles are burning point the end of a straw to one of the flames. Blow through the straw to extinguish just one of the flames. The other candle should keep burning. What happens after you extinguish one of the candles? Can you explain your observation? Repeat this step several times. Do you always get the same results?
The bluish color at the base of the flame is where the hydrocarbon molecules vaporize and start to break apart into hydrogen and carbon atoms. Some of the carbon atoms in this zone may also begin to burn to form carbon dioxide. The middle part of the flame will be a dark orange-brown due to the relative absence of oxygen.
In this area, carbon continues to break down. It also begins to form tiny hardened particles that are heated to approximately degrees Centigrade as they rise up through the flame. Next is the yellow zone, which forms the bulk of the flame and gives it the classic golden color.
In this zone, more and more carbon particles are created, which can lead to the formation of soot. These particles continue to heat until they ignite, emitting the full spectrum of light, with yellow being the most dominant to the human eye.
If you buy a length of un-waxed wick at a craft store and play with it, you will find that it feels like soft string and absorbs water very well. This absorbency is important in a candle because the wick needs to absorb liquid wax and move it upward while the candle is burning. Paraffin wax is a heavy hydrocarbon that comes from crude oil see What is the difference between gasoline, kerosene, diesel fuel, etc.? When you light a candle, you melt the wax in and near the wick.
The wick absorbs the liquid wax and pulls it upward. The heat of the flame vaporizes the wax, and it is the wax vapor that burns. You can prove that it is wax vapor, rather than liquid wax, that is burning with two experiments:. The reason the wick does not burn is because the vaporizing wax cools the exposed wick and protects it. You may have seen the camping trick of boiling water in a paper cup. The cup does not burn because the water inside cools it.
The liquid wax does the same thing for the wick. Paraffin wax will burn on its own, but it is like cooking oil, motor oil and coal in that you have to get it very hot for combustion to begin. An oil fire is intense and very hard to put out.
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