Ok I'm a little confused about why my shirt is red: so it's supposed to be that the pigments on my shirt absorb all the wavelengths besides those corresponding to red (which it reflects and which is what you see). But if my shirt absorbs those "other wavelengths", doesn't that mean electrons get excited? And when they fall back down to their original energy levels, they'll emit photons at a wavelength corresponding to their respective colors? Please help me!
Why is my shirt red?
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They get excited, but they generally don't emit photons of the same wavelength. The more probable pathway to get back to their ground state is the excited state molecules pass off some of the energy through collision with other molecules including gases in the air and radiate IR radiation of a much smaller frequency in smaller steps.
This diagram can help clarify even though it's meant to show how UV radiation results in emission of visible light, but it's a similar process.
This diagram can help clarify even though it's meant to show how UV radiation results in emission of visible light, but it's a similar process.
Hrm, that's what I thought too, but in TBR Atomic Theory for GC, it says for some answer to a related question:
"Whatever goes in, must come out for normal behavior of light. There are situations where a high-energy photon is absorbed that results in the excitation of an electron through multiple levels [such as phosphorescing species]...As a general rule, the energy that is absorbed is also emitted".
"Whatever goes in, must come out for normal behavior of light. There are situations where a high-energy photon is absorbed that results in the excitation of an electron through multiple levels [such as phosphorescing species]...As a general rule, the energy that is absorbed is also emitted".
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Are they talking about something like atomic emission spectroscopy? In that case, you're using a flame to throw a ton of energy into an atom, which makes it emit a bunch of spectra, including large transitions in the visible range or above for some elements.
They might just be saying there that an absorption spectrum has lines in the same frequencies as an emission spectrum gives off light.
EDIT and remember that your shirt contains pigments that are most likely molecules. That means they have small energy level changes corresponding to bond vibrations. This isn't present in atoms, so they can't relax with IR emissions. They have much larger gaps in energy levels.
They might just be saying there that an absorption spectrum has lines in the same frequencies as an emission spectrum gives off light.
EDIT and remember that your shirt contains pigments that are most likely molecules. That means they have small energy level changes corresponding to bond vibrations. This isn't present in atoms, so they can't relax with IR emissions. They have much larger gaps in energy levels.
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