Emission/Absorbtion Spectras

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In summary, during an experiment to find emission spectra for certain minerals and objects, the presence of white walls caused interference and confusion in the results. The absorption spectra of a green, orange, and yellow incandescent globe is expected to have a range of lines and bands, with a strong line present in the green area. For permanganate solution and chlorophyll held up to an incandescent globe, a range of lines and bands is also expected, with a strong line present in the green area. This is assuming incandescent bulbs, as vapor excitation lights have more restricted spectra.
  • #1
Exidez
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?
 
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  • #2
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.
 

1. What is an emission spectrum?

An emission spectrum is a graphical representation of the wavelengths of light emitted by a substance when it is excited or heated. Each element or compound has a unique emission spectrum, making it a useful tool for identifying substances.

2. How is an emission spectrum produced?

An emission spectrum is produced when electrons in an atom or molecule are excited to higher energy levels by an external source, such as heat or electricity. As the electrons return to their ground state, they release energy in the form of light at specific wavelengths, creating the characteristic lines of an emission spectrum.

3. What is an absorption spectrum?

An absorption spectrum is the opposite of an emission spectrum - it shows the wavelengths of light that are absorbed by a substance. This spectrum is produced when a substance is illuminated with a continuous spectrum of light and some of the wavelengths are absorbed by the substance, leaving dark lines in the spectrum at the corresponding wavelengths.

4. How is an absorption spectrum useful?

An absorption spectrum can be used to identify the presence of certain elements or compounds in a substance. The dark lines in the spectrum correspond to the wavelengths of light that were absorbed by the substance, providing a unique "fingerprint" that can be compared to known spectra to determine the composition of the substance.

5. What are some common applications of emission/absorption spectra in science?

Emission and absorption spectra have a wide range of applications in various fields of science, including astronomy, chemistry, and material science. They are used to identify elements in stars and other celestial bodies, analyze the composition of materials, and even detect the presence of pollutants in the environment.

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