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I was just reading some chemistry article and among the list of materials there was:
- hotplate or other flameless heat source (to avoid igniting the ethanol)
This made me wonder. It's basically general knowledge that things ignite more easily when you put flame to them. Why is that? It makes it seem as if flames had something more to them than just the heat, what is it?
What you say is based on your everyday experience, but not necessarily true in all situations. My friend, who performs physics experiments for kids uses parabolic reflectors, one on one side of the room to collect the heat from an electrical heat element and 'beam' about 20 feet away to to the other which focuses it on a match head to light it on fire. Some flames are relatively cool, like flaming isopropyl alcohol. Good luck trying to light paper with the flame. All materials have a flash point temperature, and so it just depends on the thermal mass and the net heat Flux to reach that temperature. A flame doesn't always have the advantage.
