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Author Topic: How does electron orbit get started?  (Read 1803 times)

Offline thedoc

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How does electron orbit get started?
« on: 14/07/2012 06:30:01 »
Aman Sharma  asked the Naked Scientists:
Electrons keep on revolving around the nucleus of atom because once it gets energy it can not be retarded until an external force is applied.

But from where do the electrons get energy initially?

What do you think?
« Last Edit: 14/07/2012 06:30:01 by _system »


Offline chris

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Re: How does electron orbit get started?
« Reply #1 on: 15/07/2012 10:33:08 »
Although it's convenient to think of atoms as consiting of a small, positively-charged, tiny-but-massive nucleus flanked by a cloud of orbiting electrons, this is a simplification. Much like photons, which are convenient to consider as particles but actually function as waves, electrons are not actually discrete point-positioned entities occupying specific orbits about the atom like satellites around a planet. Were this the case, then the electrons would be continuously having to change direction as they orbited the nucleus; this would cause them to emit radiation (like a synchrotron) and you'd have invented a perpetual motion machine! This obviously cannot be true.

Instead, electrons are considered to behave like a wave, with a probability of being in one place at any one time around the atom.

So when a proton and an electron combine to form hydrogen, no "orbit" energy is needed. The two are in a stable relationship bound by electromagnetic forces.

Thanks for the interesting question.

« Last Edit: 15/07/2012 10:35:03 by chris »

Offline Phractality

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Re: How does electron orbit get started?
« Reply #2 on: 15/07/2012 18:30:49 »
The highest potential energy state of an electron is to be completely separated from any nucleus, though it may acquire additional kinetic energy by passing thru an electric field, such as the in the back of a CRT picture tube or particle accelerator. Since a nucleus has positive charge and an electron has negative charge, there is attraction between them, and the electron's potential energy becomes kinetic as it nears a nucleus.

At closest approach, the electron has enough kinetic energy to take it past the nucleus and back to its previous free state. To enter orbit around the nucleus, it must shed some energy by emitting a photon. I doubt if the exact mechanism of emitting a photon is fully understood. We only know that the electron must shed exactly enough energy to put it into one of the relatively stable orbitals. If it ends up in a higher orbital, it will soon fall to a lower orbital by emitting an additional photon of a specific wavelength.
« Last Edit: 15/07/2012 18:32:59 by Phractality »

Offline Soul Surfer

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Re: How does electron orbit get started?
« Reply #3 on: 16/07/2012 00:18:19 »
The electrons get their energy to enter an orbital from the electrostatic attraction between the negatively charged electron and the positively charged nucleus in fact they have to loose energy by emitting quanta to become trapped in an orbital.

Note, orbital, is the name given to the stable state with an electron locked in a volume around a nucleus.  it is a bit like a resonant cavity the electron has a diffuse probability function associated with the orbital.  this is precisely defined in size and shape it is not an orbit like a planet around a star.

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Re: How does electron orbit get started?
« Reply #3 on: 16/07/2012 00:18:19 »


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