When are electrons excited vs ejected

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EmilyC_3D
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When are electrons excited vs ejected

Postby EmilyC_3D » Fri Oct 16, 2020 1:30 pm

I think I basically understand the difference between when an electron is excited vs when it is ejected. However, I'm not totally sure how to tell in which situation each one could occur. Would anyone be able to explain that difference? Thank you!

Brennan McGurrr 3C
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Re: When are electrons excited vs ejected

Postby Brennan McGurrr 3C » Fri Oct 16, 2020 1:59 pm

The difference is there are two different experiments that result in each. Electrons are ejected in a Photoelectric Effect experiment when light causes the pool electrons of metals to be ejected. In an atomic spectroscopy experiment, the light causes the electrons in a particular atom to become excited and increase energy levels. I hope this helps.

Sana Nagori 2H
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Re: When are electrons excited vs ejected

Postby Sana Nagori 2H » Fri Oct 16, 2020 2:05 pm

So I think electrons will be "excited" if there is ever an input of energy. However, they will only ever eject if the incoming energy from the photon is either equal to or greater than the work function value (energy needed to eject electron).

Tatyana Bonnet 2H
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Re: When are electrons excited vs ejected

Postby Tatyana Bonnet 2H » Fri Oct 16, 2020 2:10 pm

Electrons are excited when energy from the photon is present but does not exceed the threshold/work function resulting in the electrons to jump energy levels (excited). The electron is ejected when the amount of energy exceeds the threshold/work function.

Charisma Arreola 2F
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Re: When are electrons excited vs ejected

Postby Charisma Arreola 2F » Fri Oct 16, 2020 2:36 pm

An electron is only ejected if it has become too excited for the current level it is in, and can not jumo into a new level.

emmaferry2D
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Re: When are electrons excited vs ejected

Postby emmaferry2D » Fri Oct 16, 2020 2:47 pm

think of the equation E(photon)= Ek+ work force
This means that the E(photon) must be greater than or equal to the kinetic energy of the electron plus the work force in order to eject the electron. If the energy of the photon is less than this then it will just excite the electron and lead in no ejection.

Emily_Stenzler_2H
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Re: When are electrons excited vs ejected

Postby Emily_Stenzler_2H » Fri Oct 16, 2020 2:50 pm

One of the UAs also said to visualize the following: if any energy is inputted, the electrons will be 'vibrating' and moving around. Once the energy input is equal to or greater than the work function, then the electrons will be fully ejected from the metal they were on.

Alen Huang 2G
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Re: When are electrons excited vs ejected

Postby Alen Huang 2G » Fri Oct 16, 2020 2:57 pm

Electrons are only ejected when the incoming energy is greater than the work function but electrons can be excited with any amount of energy, given that it is enough to jump at least one energy level, before that.

Jessica Manriquez 1H
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Re: When are electrons excited vs ejected

Postby Jessica Manriquez 1H » Fri Oct 16, 2020 4:35 pm

electrons would be ejected when talking about the photoelectric effect, which is why the detector served to couldn't the number of electrons that were ejected; in the atomic spectroscopy experiment youre basically trying to measure at which frequency the electrons get excited into a next level; hence photoelectric effect=ejected and atomic spectroscopy= excited

Emma Chang 1G
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Re: When are electrons excited vs ejected

Postby Emma Chang 1G » Fri Oct 16, 2020 11:28 pm

In the photoelectric effect, I think electrons are ejected as long as the energy of an individual photon is greater than or equal to the threshold energy, or the amount of energy needed to eject an electron from the metal surface.
In an atomic spectroscopy experiment, the electron is excited when the energy of the photon matches the difference between energy levels. Hope this helps!

Tanner Bartyczak 1K
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Re: When are electrons excited vs ejected

Postby Tanner Bartyczak 1K » Sat Oct 17, 2020 11:20 pm

This is also how I understood it. Good to know the difference, though.

Norah Gidanian 3D
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Re: When are electrons excited vs ejected

Postby Norah Gidanian 3D » Sat Oct 17, 2020 11:27 pm

All of these replies are really helpful! I think that an electron is ejected once it is really far away from the nucleus that it doesn't have a pull towards it. When an electron is excited, it still has some pull towards the nucleus and will come back down.

Eliana Carney 3E
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Re: When are electrons excited vs ejected

Postby Eliana Carney 3E » Sun Oct 18, 2020 12:54 am

Electrons are excited during atomic spectroscopy when they go from one energy level to another. They are ejected during the photoelectric experiment when the goal is to measure how much energy is required to remove electrons from different metals.

Carolina Gomez 2G
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Re: When are electrons excited vs ejected

Postby Carolina Gomez 2G » Sun Oct 18, 2020 5:06 pm

In atomic spectroscopy, electrons become excited when the energy of the light source is equal to the energy difference needed for the electron to move to a higher energy level (n). If electrons are ejected, the incoming photon is equal to or greater than the threshold energy/ work function, which would result in the ejected electrons in the photoelectric effect.

Lily Carlson 1K
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Re: When are electrons excited vs ejected

Postby Lily Carlson 1K » Sun Oct 18, 2020 5:34 pm

Another perspective to think about this is that if the electrons receive enough energy to be ejected (thus creating the photoelectric effect), the electrons contain so much energy to where the atoms can no longer contain them. In contrast, excitable electron should still be within atoms, and the dropping of the energy states causes the emission of light.

Claudia_Danysh_2B
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Re: When are electrons excited vs ejected

Postby Claudia_Danysh_2B » Sun Oct 18, 2020 6:39 pm

Hi! So my understanding is that an electron is excited when it receives energy from an incoming photon and because of this is "excited," ultimately making the electron jump to a higher energy level. Sometimes, when this energy from an incoming photon is high enough, the electron is so "excited" that it is excited past every energy level within the atom in question and ends up being ejected. Hope this helps!

Ayesha Aslam-Mir 3C
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Re: When are electrons excited vs ejected

Postby Ayesha Aslam-Mir 3C » Mon Oct 19, 2020 1:04 am

One thing I have a question about is why the electron goes up and them combes back down when excited by a photon; I understand the Zeff or charge of the nucleus may pull the elctron back down energy levels, but could photos also just ionize atoms, as in causing them to lose their electrons entirely? Would a high frequency wave be able to ionize atoms?


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