posted by jenna on .
why does a candle appear to go out when a copper coil is placed over the flame?
Combustion requires three things: fuel (wax here), oxygen (air here),
ignition temperature (a match here probably). Remove one and the combustion
stops -- that's the principles firemen use to put out fires. In the case of
your candle the high thermal conductivity of copper probably is conducting
sufficient heat from the flame that the flame goes out, but the heat
capacity of the melted wax, wick, etc. probably "holds" enough heat that the
temperature exceeds the ignition temperature if the copper wire is removed.
If this mechanism is operating you can test it by holding the copper coil
around the flame area for some time, so that the molten wax and wick cool,
the flame will not re-ignite when you remove the copper coil