Chemistry Help Forum How does electrons do not fall into the nucleus

 Mar 31st 2017, 08:19 AM #1 Nannan Junior Member   Join Date: Mar 2017 Location: Tamilnadu Posts: 1 How does electrons do not fall into the nucleus I have an doubt How can an electron keep revolving without falling into nucleus by losing energy? Some one please explain
Mar 31st 2017, 09:23 AM   #2
topsquark
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 Originally Posted by Nannan I have an doubt How can an electron keep revolving without falling into nucleus by losing energy? Some one please explain
Sounds like you are discussing the Bohr model of the atom?

In the early 1900s, when Bohr first worked out the general construction of the atom there was no reason that the electron shouldn't fall into the nucleus. It was an assumption that had to be put into the theory. The rule is kind of ad-hoc and has no other purpose than to try to sweep the issue under the proverbial carpet.

Basically the idea is that, just as happens with the planets, we can have the electrons orbiting the nucleus. This is formalized by the de Broglie wavelength (another major accomplishment). It says that the electron is a wave and in order to make any sense has to orbit it has to go around in a coherent fashion: it has to end up where it began or the wave would go away via destructive interference.

So if we have an electron with a wavelength (lambda) then the radius of the electron's orbit would have to be n(lambda) = 2 (pi) r, where n is a positive integer.

-Dan
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Apr 3rd 2017, 10:30 AM   #3
MatthijsM
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 Originally Posted by Nannan I have an doubt How can an electron keep revolving without falling into nucleus by losing energy? Some one please explain
Simple explanetion: The positive charge of the protons is equal to the negative charge of the electrons which results in a netto force of 0 and that is why they do not lose energy.

Apr 3rd 2017, 02:04 PM   #4
topsquark
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 Originally Posted by MatthijsM Simple explanetion: The positive charge of the protons is equal to the negative charge of the electrons which results in a netto force of 0 and that is why they do not lose energy.
I'm afraid it isn't that simple. Seeing as two unlike charges attract one would suspect that the electron does move inward. If we are using the Bohr atom then we have that the electron is moving in a curved path, and charges moving in a curved path (ie accelerating) emit photons the electron loses kinetic energy. (This is even true Classically.)

The fact that the electron doesn't lose energy in the Bohr model caused a fair amount of criticism.

-Dan
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What is the name of the molecule CH2O?