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Author Topic: Why would something turn black upon combustion/ burning?  (Read 11975 times)

Offline The Scientist

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Please give the answers as detailed as possible. Thank you.


 

Offline Eric A. Taylor

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Why would something turn black upon combustion/ burning?
« Reply #1 on: 30/06/2010 21:37:37 »
Everything that turns black when burned is largely made of carbon. When you burn a bit of wood, or your chicken dinner (or any other type of food) what you are left with is mostly carbon. This happens when there is not enough oxygen to completely burn all the carbon. If you see a truck (and sometimes older jet airplanes) when they go to full power spew out lots of black smoke they are not completely burning the fuel.

This was a problem with the J-79 jet engine used in the F-4 Phantom. The engine smoked badly, which is bad for a fighter, it helps the enemy find you. The engines did not smoke when the afterburner was lit.
 

Offline The Scientist

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Why would something turn black upon combustion/ burning?
« Reply #2 on: 01/07/2010 13:22:36 »
Everything that turns black when burned is largely made of carbon. When you burn a bit of wood, or your chicken dinner (or any other type of food) what you are left with is mostly carbon. This happens when there is not enough oxygen to completely burn all the carbon. If you see a truck (and sometimes older jet airplanes) when they go to full power spew out lots of black smoke they are not completely burning the fuel.

So Eric A. Taylor, am I correct in saying that carbon is black? Thanks
 

Offline Eric A. Taylor

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Why would something turn black upon combustion/ burning?
« Reply #3 on: 02/07/2010 10:33:07 »
Everything that turns black when burned is largely made of carbon. When you burn a bit of wood, or your chicken dinner (or any other type of food) what you are left with is mostly carbon. This happens when there is not enough oxygen to completely burn all the carbon. If you see a truck (and sometimes older jet airplanes) when they go to full power spew out lots of black smoke they are not completely burning the fuel.

So Eric A. Taylor, am I correct in saying that carbon is black? Thanks

Most of the ways we encounter pure carbon it looks black. Sometimes if the atoms are arranged in the right way it will be transparent. This is called "diamond" is is considered to be quite valuable.
 

Offline sithcdw

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Why would something turn black upon combustion/ burning?
« Reply #4 on: 07/07/2010 07:16:02 »
when an object is burned, such as wood, chicken, etc., the object turns black because of the carbon residue left behind. Organic materials are largely made of hydrocarbons which, wehn subjected to a high energy source, split apart into their counterparts. some of the carbon combines with oxygen to create CO2 and CO and the Hydrogen combines with Oxygen to create H2O. Some other very minute chemicals are released as well, however in a combustion reaction the main compounds created are CO2 and H2O. After burning, some of the carbon is left over, that is what we see as the black substance.
Now you may have noticed if you expose a glass beaker ot test tube to an open flame, the bottom turns black. This is because the hydrocarbons within the flames fuel separate and react with the oxygen in the air, again creating H2O and CO2, however some carbon gets "stuck" on the glass.
« Last Edit: 07/07/2010 07:18:46 by sithcdw »
 

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Why would something turn black upon combustion/ burning?
« Reply #4 on: 07/07/2010 07:16:02 »

 

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