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Emission/Absorbtion Spectras

  1. Sep 12, 2003 #1
    I recently did an experiment at school to find the emission spectra for certain minerals and objects. Because we didnft do it in a pitch black room we had a lot of interference of the white walls which really confused results.
    So I was just wondering what the absorption spectrafs would be of a green, orange and yellow incandescent globe. Will you just see green bands for the green globe, yellow bands for the yellow globe ect..?

    Also what will be absorption spectrafs of a permanganate solution and chlorophyll held up to an incandescent globe?
  2. jcsd
  3. Sep 13, 2003 #2


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    As you no doubt already know, the emission lines and bands are produced by excitation of specific elemental atoms (or absorption by the same kind of atoms). Your eye builds its color representation (what you see) from just the sampled intensities at two specific frequencies - in the blue green and red. From this is reconstructed a colored image, but the world outside doesn't have that color, it has the full range of incident light frequencies.

    So my prediction is you will see a range of lines and bands in all parts of the spectrum, but with a strog line present in the green area. or a combination that makes the color. This is assuming incandescent bulbs. Vapor excitation lights have much more restricted spectra. A sodium vapor light for example puts most of its energy into the famous sodium line(s) in the yellow.
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