Why does the colour of smoke depend on the fuels that you burn?

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Why does the colour of smoke depend on the fuels that you burn?

In: Chemistry

“Smoke” is not one substance, it’s just the collection of whatever solid and liquid particles get airborne when something burns, a mix of burned and unburned material. Fire is a chemical reaction between oxygen and fuel (whatever is burning). So naturally, the chemicals you get out depend on the chemicals you put in.

When a chemical burns or there’s a chemical reaction, electrons in the atoms get excited and jump up to higher energy levels, and release photons when they fall back into their original place. Different chemicals/ fuels release different frequencies of photons because they have different arrangements of electrons.

E: like others have pointed out, this explains the flame color, but not really the smoke color. Smoke no longer radiates light in the visible spectrum in the way I described above, so the color of the smoke is just the color of whatever byproduct the reaction produces.