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aditya23456
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why does peak of fire of a matchstick face upwards ie away from ground.why is it not effected by gravity,is there any reason other than pressure considerations.
Antiphon said:It's made of the vapors of the burning object plus oxygen from the air.
mkillman said:fire is light emitted by the excited atoms of the material when excited to the point of combustion
mkillman said:the "flame" is nothing more then light from atoms that have been excited to the point where they begin an exothermic reaction with the air around them
Fire is the rapid oxidation of a material
The flame is the visible portion of the fire
mkillman said:yes there are several materials that burn off into UV instead of visible light
aditya23456 said:can a flame be in such a way that it gives out only light of frequencies other than visible light..I meant flame exists but its hardly visible to human eye
Lsos said:Someone correct me if I'm wrong, but the flame is not made up of any particularly special atoms or substance. It is simply a regular substance, such as air, that has been heated to the point that it releases light.
Lsos didn't say "just air", he said "such as air" which allows other things.Borek said:You are right about "nothing special", but it is not "just air". Think combustion products.
Antiphon said:It's made of the vapors of the burning object plus oxygen from the air.
Antiphon said "vapors of the burning object" which Merriam-Webster defines as "diffused matter (as smoke or fog) suspended floating in the air and impairing its transparency"Borek said:So there is no combustion products in the flame? If so, where does the energy heating the flame comes from?
Enthalpy of formation of H20 is -242kJ/mol. That's enough to heat water vapor to at most 7k K. (Realistically, significantly less.) This is still well within visible band. The reason you don't see the flame is because it also happens to be very close to the minimum in absorption spectrum for H2O, so the emission intensity is very low.Delta Kilo said:Note how hydrogen flame from the main engines is almost invisible, especially in comparison with solid propellant SRBs.
Fire is a chemical reaction that involves the rapid combination of oxygen with a fuel source, such as wood or gasoline.
Fire is actually considered a plasma, which is a state of matter that occurs when gas is heated to such a high temperature that it ionizes and becomes electrically conductive.
The elements that make up fire are carbon, hydrogen, and oxygen. These elements are present in most fuel sources, and they combine with oxygen in the air to produce fire.
Atoms are the building blocks of all matter, including the elements that make up fire. During a fire, atoms in the fuel source break apart and recombine with oxygen atoms, releasing energy in the form of heat and light.
No, fire cannot exist without oxygen. Oxygen is a necessary component for the chemical reaction of fire to occur. Without oxygen, the fire will go out or will not be able to start in the first place.