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Temperature of a Blue Flame

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Bibliographic Entry Result
(w/surrounding text)
"Flame Analysis." Macmillan Encyclopedia of Chemistry. New York: Simon & Schuster, 1997: 626. "the temperature is 2,950–3,050 °C" 3,220–3320 K
Gaydon & Wolfhard. Flames: Their Structure, Radiation and Temperature. 4th ed. New York: Halsted, 1979: 155, 244-245. "1000 °C, 8000 °C" 1270 K
8270 K
"This very high sensitivity of the method is due to the rapid variation of light intensity with temperature; at 2,500 K and 5890 Å" 2500 K
Fristrom & Westenberg. Flame Structure. New York: McGraw Hill, 1965: 155. "1,750 °C 1,800 °C 1,820 °C" 2020–2090 K

Fire was first used by the caveman as a source of heat. Even in modern day, we still use fires (candles, Bunsen burners, and gas flames for cooking). These types of fire are actually processes of oxidation. Oxidation is the combination of oxygen with another material. When the combination of oxygen and the other material is so fast that it produces a flame, it is called combustion.

To cause combustion, heat must be added to the object until it reaches a certain temperature called the ignition point. Not only does each material has to reach a different temperature before it is ignited, it also depends upon the conditions of the environment (weather, amount of gas around the object, etc.). These factors are so dependent that when acetylene is ignited in air, it reaches a temperature of 2,200 °C to 2,400 °C. If it is ignited in pure oxygen, it reaches a higher temperature of 2,950 °C to 3,050 °C. Flames also have different areas of temperature, even in an ordinary candle, the temperatures are separated into several different regions. The regions are also separated by color, the blue region (the innermost part of the flame) being the hottest. This shows there is not one precise temperature for a blue flame.

James Danyluk -- 1998

Bibliographic Entry Result
(w/surrounding text)
Lyons, John W. Fire. New York: Scientific American Books, 1985: 60.
Some Calculated Adiabatic Flame Temperatures*
Absolute temperature (K)
Acetylene in air 2,600
Acetylene in oxygen 3,410
Methane in air 2,232
Methane in oxygen 3,053
Hydrogen in air 2,400
Hydrogen in Oxygen 3,080
Heptane in air 2,290
Heptane in oxygen 3,100
From Glassman.
*Assumes fuel and oxidizer begin at room temperature.
2232–3410 K
McGee, Harold. On Food and Cooking: The Science and Lore of the Kitchen. New York: Fireside, 1984: 614. "Glowing coals or the nickel-chrome alloys used in electrical appliances reach about 2000 °F (1093 °C), and a gas flame is closer to 3000 °F (1649 °C). The walls of an oven, by contrast, rarely exceed 500 °F (269 °C)." 1900 °C

Editor's Supplement -- 2001

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