Stupid question about electron orbitals

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I've haven't taken a chemistry course as of yet, so I'm probably getting something very wrong here, but one thing that someone said confused me.

They said that when an electron changes it's orbital, it emits a photon.

I like to think about orbitals (and I know that this is ONLY a useful analogy) where electrons are handballs, the nucleus is the earth, and the handball want to fall as close to the earth as possible. If you pump energy (in the form of photons) into the atom, you raise the handball/electron further from the earth (increasing its potential energy). Then, the electron will fall back down to the nucleus, and this energy, instead of manifesting itself in kinetic energy, manifests itself in a photon which is released from the atom.

But why would an atom release a photon when the electron INCREASES its orbital? Am I misinterpreting what they said, or is this where my helpful analogy breaks down?
 

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  • #2
Pengwuino
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What do you mean, increases its orbital?
 
  • #3
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What do you mean, increases its orbital?
Sorry- I mean that if in hydrogen, the electron is the the first orbital, and in Lithium (number 3) two electrons are in the first orbital and one is in the second. As the orbitals progress, the electrons in said orbitals get further and further away from the nucleus.

Like, if you want to think about the Sun and planets, Mercury is an electron in the first orbital, and Venus is the second, Earth the third, and so on. Is that clear?
 
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  • #4
cepheid
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Energy has to be conserved. A photon is only emitted if an electron moves from a higher energy level to a lower one. The energy of the emitted photon is equal to the difference between the two energy levels.

If an electron is to move from a lower energy level to a higher one, it must gain an amount of energy equal to the difference between the two levels. This energy has to come from somewhere. So this process can't happen spontaneously. But it can happen if an *incoming* photon of the right energy is absorbed by the electron, exciting it to the higher energy level.
 
  • #5
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Energy has to be conserved. A photon is only emitted if an electron moves from a higher energy level to a lower one. The energy of the emitted photon is equal to the difference between the two energy levels.

If an electron is to move from a lower energy level to a higher one, it must gain an amount of energy equal to the difference between the two levels. This energy has to come from somewhere. So this process can't happen spontaneously. But it can happen if an *incoming* photon of the right energy is absorbed by the electron, exciting it to the higher energy level.
Oh, ok, so my intuition was right. :)
One questions- does this have to do with why hot things glow? Is energy in the form of photons the same as kinetic energy of the atom caused by heat, shifting electrons fro higher to lower orbits and in the process producing photons? (Both infra-red and visible)
 

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