Say charcoal, a very combustible substance, reacts with oxygen and lights on fire. What starts the reaction though? I'm aware that the actual fire (combustion) part is when charcoal would combine (react) with oxygen, but it's not like charcoal that's sitting around just automatically lights on fire all the time. I'm sorry if my question seems ignorant.
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The match heat input comes from friction with the striker against the match. The energy to strike the match comes from the combination of glucose and oxygen creating energy in the muscles of the wrist that strikes the match. That glucose comes from the photosynthesis of plant material that is consumed by the body. The photosynthesis in turn is caused by the sun. The light from the sun is a result of the continuous fusion reaction in the sun's core.
Summary: The heat of ignition ultimately comes from a thermonuclear reaction on the sun.
Summary: The heat of ignition ultimately comes from a thermonuclear reaction on the sun.
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The complete reaction looks something like C + O2 + q ---> CO2 + Q; I'll explain.
C is the charcoal, it's mostly carbon; thus the C. And a little bit of heat, q, is added; such as putting a match to the charcoal bricks. That causes the carbon and the oxygen in the air to combine chemically into carbon dioxide, the CO2, and give off even more heat, the heat of combustion Q.
While most of that Q goes into the air to cook the BBQ, some of that extra heat becomes the q on the LHS of the reaction to react with some of the remaining charcoal bricks, which creates more BBQ heat to burn the burgers and q to burn more C, and the cycle goes on and on until all the C is more or less burned up (oxidized) and becomes ash. Oh, the burgers came out fine.
C is the charcoal, it's mostly carbon; thus the C. And a little bit of heat, q, is added; such as putting a match to the charcoal bricks. That causes the carbon and the oxygen in the air to combine chemically into carbon dioxide, the CO2, and give off even more heat, the heat of combustion Q.
While most of that Q goes into the air to cook the BBQ, some of that extra heat becomes the q on the LHS of the reaction to react with some of the remaining charcoal bricks, which creates more BBQ heat to burn the burgers and q to burn more C, and the cycle goes on and on until all the C is more or less burned up (oxidized) and becomes ash. Oh, the burgers came out fine.