Rather than answering all the individual requests I am getting, let me
post some details of the "Sodium Line Reversal experiment":
Bend the end of a platinum or iron (unpainted coat hangar) wire into a
small hook and fill the hook opening with a mush of water and Na2B4O7
(Borax) ... NaCl should work also. Hold the hook in a bunsen flame
and the Borax will fuse into a bead. Shine the beam from a collimated
optical bench type white light source through the flame
(just above the Borax) and into the entrance slit of a spectrometer.
Vary the voltage supplying the light source and watch the Sodium
lines reverse.
-Bob
********************************
This reminds me of an experiment we used to do: Examine the spectrum
of an incandescent bulb shining through a sodium (NaCl) flame and then
into the spectrometer entrance slit. Vary the temperature of the
incandescent bulb with a variac and watch the sodium lines go from
emission (bright) to absorption (dark) as seen against the continuous
spectrum.
******************************
Bob Sciamanda sciamanda@edinboro.edu
Dept of Physics trebor@velocity.net
Edinboro Univ of PA http://www.edinboro.edu/~sciamanda/home.html