How come an electron doesnt collide with a proton?

[iAmSchrodinger'sCAT]

If I am right (which I hope I am) a positive charge is attracted to a negative charge and vice verse. So how come the electron doesn't come crashing down on the nucleus because its protons. I understand that the nucleus has an overall neutral charge. But what about isotopes they can have a positive charge? So why don't we see electrons bombarding our nucleus?

[rktpro]

I understand that the nucleus has an overall neutral charge.

 

Nucleus is positively charged.

[lemur]

My understanding of quantum physics is that electrons are limited to fixed levels about the nucleus and that the lowest level is a "ground state" that can't further degenerate into collapse with the nucleus. I believe the bohr model of the atom as a planetary-like system was discredited for the reason that electrons would collapse into the nucleus as they radiated their kinetic energy away as light. So I think it might have been Planck who found that they changed levels in fixed amounts or "quanta" and that they could only emit energy by dropping to a lower level or absorb energy by moving to a higher level.

[steevey]

If I am right (which I hope I am) a positive charge is attracted to a negative charge and vice verse. So how come the electron doesn't come crashing down on the nucleus because its protons. I understand that the nucleus has an overall neutral charge. But what about isotopes they can have a positive charge? So why don't we see electrons bombarding our nucleus?

 

Because an electron has wave-like properties, and those wave-like properties allow the electron to exist in regions around the nucleus without any classical trajectory but in still most-probable regions. Also, things on that scale individually are really weak. The electromagnetic pull of a single proton really isn't that strong at all, so even a little bit of energy can cause a lot of commotion as the lack of strength on that level doesn't inhibit electrons enough to fall straight into the nucleus. Electrons are also a lot less massive, nearly 2000 times less massive than protons, so that means a little energy in an electron can cause an electron to move a lot more easily.

Edited April 14, 2011 by steevey

[swansont]

My understanding of quantum physics is that electrons are limited to fixed levels about the nucleus and that the lowest level is a "ground state" that can't further degenerate into collapse with the nucleus. I believe the bohr model of the atom as a planetary-like system was discredited for the reason that electrons would collapse into the nucleus as they radiated their kinetic energy away as light. So I think it might have been Planck who found that they changed levels in fixed amounts or "quanta" and that they could only emit energy by dropping to a lower level or absorb energy by moving to a higher level.

 

No, the Bohr model was a proposed solution to this problem.

 

Because an electron has wave-like properties, and those wave-like properties allow the electron to exist in regions around the nucleus without any classical trajectory but in still most-probable regions. Also, things on that scale individually are really weak. The electromagnetic pull of a single proton really isn't that strong at all, so even a little bit of energy can cause a lot of commotion as the lack of strength on that level doesn't inhibit electrons enough to fall straight into the nucleus. Electrons are also a lot less massive, nearly 2000 times less massive than protons, so that means a little energy in an electron can cause an electron to move a lot more easily.

 

Isn't strong as compared to what? The purported "lack of strength" is not the reason.

 

If I am right (which I hope I am) a positive charge is attracted to a negative charge and vice verse. So how come the electron doesn't come crashing down on the nucleus because its protons. I understand that the nucleus has an overall neutral charge. But what about isotopes they can have a positive charge? So why don't we see electrons bombarding our nucleus?

 

That's one of the big questions of atomic structure that gave rise to quantum mechanics, and as I mentioned above, one of the motivations behind the Bohr model.

 

Electrons do bombard the nucleus, but they pass right through it. It's not possible to confine the electron to the nucleus with the energy (and thus momentum) it has (from the heisenberg uncertainty principle), and because energy is quantized, it isn't possible for the electron to shed energy. (The only possibility is to combine with the proton, and that has to be energetically favorable is is still a fairly rare interaction)

[steevey]

Isn't strong as compared to what? The purported "lack of strength" is not the reason.

 

 

Obviously not as strong as a substance on a macroscopic scale. On a macroscopic scale, gravity is strong, magnets have greater distances, and as a result matter is more calculable on that scale. But forces and matter on the atomic scale are so small and minuscule they start to act a little like nothingness itself. An electron is really really close to nothing, its mass is very small, and as a seeming result, is wave occupies a greater areas, or in other words, theres much greater areas of probability which it is spread out over. But something like a rock, thats really big, so the most probable place of the rock itself doesn't really spread over any distance, its more or less congruent to itself and tends to act like a solid object.

Edited April 14, 2011 by steevey

[swansont]

Obviously not as strong as a substance on a macroscopic scale. On a macroscopic scale, gravity is strong, magnets have greater distances, and as a result matter is more calculable on that scale. But forces and matter on the atomic scale are so small and minuscule they start to act a little like nothingness itself. An electron is really really close to nothing, its mass is very small, and as a seeming result, is wave occupies a greater areas, or in other words, theres much greater areas of probability which it is spread out over. But something like a rock, thats really big, so the most probable place of the rock itself doesn't really spread over any distance, its more or less congruent to itself and tends to act like a solid object.

 

We aren't talking about a macroscopic scale (where charge neutrality — in part because electrostatic forces are strong — is the reason we don't see the effects), we're talking about the attraction between a proton and electron. We can calculate this, if needed to show that some effect is there or not, rather than handwaving.

 

I don't know how to sugarcoat this: You don't have training in physics. Perhaps you should reconsider trying to answer physics questions. Guesswork presented as expertise does more harm than good.

[mooeypoo]

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Moderator Note

Please stick to the topic of the thread.

Steevey's question, being off topic, was split to this thread: http://www.scienceforums.net/topic/56511-effects-of-gravity/

[Phi for All]

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Moderator Note

lemur's off-topic speculations regarding the atom have be split off into a new thread at http://www.scienceforums.net/topic/56512-a-speculative-model-of-the-atom/.

Please stay on topic.

[michel123456]

(...)

Electrons do bombard the nucleus, but they pass right through it. (...)

 

Why don't we see that in orbitals diagrams?

[farmboy]

Why don't we see that in orbitals diagrams?

 

How do you mean dude? Like the type of diagram that shows the way the electrons in molecules arrange themselves (series of lines with arrows in the different places) or as in the actualy picture of what the atomic/molecular orbitals look like. Or something else completely lol?

[michel123456]

How do you mean dude?

You can call me Michel.

Like the type of diagram that shows the way the electrons in molecules arrange themselves (series of lines with arrows in the different places) or as in the actualy picture of what the atomic/molecular orbitals look like. Or something else completely lol?

 

Like the one in your post #6 of the brother thread.

[farmboy]

You can call me Michel.

 

 

Like the one in your post #6 of the brother thread.

 

Ah cool, I don't really know the answer, but if I had to speculate I'm not sure that those types of orbital diagrams really cover that area. They basically just show the orbital where electons of certain energies are likely to be found, though they can be found elsewhere in the universe.

[swansont]

Why don't we see that in orbitals diagrams?

 

???

 

We do. The s orbitals do not vanish near r=0, and nuclei have finite size.

[michel123456]

???

 

We do. The s orbitals do not vanish near r=0, and nuclei have finite size.

 

Then I didn't interpret the diagrams correctly. I thought the orbital was only the outer surface of the "bubbles".

[steevey]

 

???

 

We do. The s orbitals do not vanish near r=0, and nuclei have finite size.

 

If electrons already do harmlessly pass through the nucleus, then what exactly does it take to get them to collide? A particle collider? Why does that make a different?

[swansont]

If electrons already do harmlessly pass through the nucleus, then what exactly does it take to get them to collide? A particle collider? Why does that make a different?

 

 

My answer was in a part that got split off

 

http://www.scienceforums.net/topic/56512-a-speculative-model-of-the-atom/page__p__601509#entry601509