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What color light do we see on the emission spectrum from an element?


alpha6

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I am reading about the emission spectrum; an electron returning to its resting state emits a wavelength associated with a color.

My question is, since there are generally several bands of color present themselves for each element, which one do we see when we put a flame to an element?

For example, if there is a red, green, and violet band, will the light we see be red, green, or violet? Thank you.

Thank you.

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3 hours ago, alpha6 said:

I am reading about the emission spectrum; an electron returning to its resting state emits a wavelength associated with a color.

My question is, since there are generally several bands of color present themselves for each element, which one do we see when we put a flame to an element?

For example, if there is a red, green, and violet band, will the light we see be red, green, or violet? Thank you.

Thank you.

It's not just the ground state. In hydrogen, for example, the visible transitions are those going to the n=2 state. (the ones going to the ground state are in the UV). So there are a lot of transitions involved, and we see some fraction of them, that are in the visible part of the spectrum.

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12 hours ago, alpha6 said:

My question is, since there are generally several bands of color present themselves for each element, which one do we see when we put a flame to an element?

You will see the result of those colours being mixed together.

Here is a page with lots of spectra: http://astro.u-strasbg.fr/~koppen/discharge/

If you look at sodium, you can see a bright pair of emissions lines in the yellow. So we see yellow.

In the case of xenon, there are lines throughout the spectrum and we see weight light from a xenon lamp.

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Been there, did the experiment, got the eyestrain. The OP seems to be smushing together two different "ways of looking" at the light.

First off, you have a burning sample (or a gas sample in capsule with high voltage). That glows and you see a single color. Purple is the one I most remember, hydrogen or one of the noble gases.  That color is all the wavelengths the sample is emitting, mixed together. So that's "look one".

Now, let's put a prism between you and the glow. You now see a set of bright lines, each line being a single wavelength., and so a single color (it is possible that you will still see a line the same color in part one, but I think that is only if the purple spectral line is much much brighter than any others)

Oh, and a word of warning with that page of spectra. If you do the experiment, you do not see "dim background full spectrum with bright lines". You see only the lines. So those images are a little misleading.  The main page doesn't mention it, but if you click on a spectra it includes the disclaimer...

Quote

Note that a faint continuum was added only to give a better impression of the location of the colours in the spectrum

 

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2 minutes ago, Chopsticks said:

Oh, and a word of warning with that page of spectra. If you do the experiment, you do not see "dim background full spectrum with bright lines". You see only the lines. So those images are a little misleading.  The main page doesn't mention it, but if you click on a spectra it includes the disclaimer...

Good point.

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