What keeps electrons from falling into the nucleus of an atom?

Question

And a related question, what happens when an electron collides with a proton?

Answer 1

That's actually a very interesting question. I assume you're thinking that since they're attracted because of their opposite charges, they'll just run into each other.

What happens is this. In reality, the electron is a localized particle only when you look at it. Otherwise, it has a wave function that obey to the Schrodinger equation. If you solve that equation for a charged particle in a 1/r^2 field, you'll get various shapes of orbits, depending on the energy. In clear, it's the energy of the electron that keeps it from crashing.

You might point out that it's not a perfect field, since the electron and proton are moving, but that was solved by Dirac a bit later.

Also, we don't really know what happens when you collide the 2. Probably nothing. When you want to create a collision, you only have to throw the electron really hard at the proton and it might hit it. When a neutron decomposes, it create a photon, an electron, an neutrino and a proton. So, when you collide them, it doesn't do much because you're missing 2 elements to create the opposite reaction.

Here is an example of actual orbitals of electrons around a proton
http://www.falstad.com/qmatom/

Answer 2

The planetary orbit analogy has no longer been the accepted model for quite some time now. The current model has electrons travelling more or less at random. They can enter the nucleus in this model. A neutron is created when an electron is captured by a proton. A neutron can also eject an electron, thus becoming a proton.

Answer 3

my friends, there is no centripetal force for the orbital electrons. that would imply that newtonian physics applies for particles as small as electrons. at this level of size, newton's three laws are almost completely useless.

in fact, to assume that electrons are orbiting the nucleus is already flawed concept. electrons do not orbit the nucleus per se. that is only a basic way of visualising the atom. the only reason why we teach this obselete understanding in schools is because there is no simpler explanation for children. there is no orbit, only a cloud of probability where the electron could possibly be at any point in time. since scientists know not of how electrons move in an atom, they also have no idea as to why they do not crash into the nucleus.

for your second question, im glad i have a better answer for you. when an electron meets a proton, they combine, forming a neutron and a neutrino.

Answer 4

What/Who gave the electrons the speed needed to keep themselves from falling into the nucleus? An fuzzy elephant. A Snuffleupagus. Let's run with your idea though. So there IS an omnipotent creator. OK. So, this creator is ALL powerful, created us, created the universe, made all the rules, knew all of the future, in short, this 'God' gets what he wants. Whatever he wants, he gets. Well, look around. Read the news. What does your 'God' want ? Apparently, he wants a never ending flood of evil and atrocity. He wants carnage both from his worshipers and from his natural forces and from genetics (oh, and from atheists, I won't try to dodge that). He wants life to be suffering and struggle that always ends in death and THEN, according to you, he wants to punish people for not sucking up properly. Ok, fine, go worship that. Knock yourself out.

Answer 5

A very good question! To answer this question Bohr has invented quantum mechanics of the Hydrogen atom (http://www.thebigview.com/spacetime/quantumtheory.html). He used otherwise ideas which have started by Planck and where given some realization by Einstein and extended them to the realm of the atom in order to answer this very question. Formally he has extended Planck's quantization principle from energy to angular momentum.
There is an electron-proton collider in Hamburg (HERA) where with the help of a few detectors (ZEUS, H1) physicists try to research the laws of small scale physics (http://www-hera-b.desy.de/general/info/).

Answer 6

I think K-biz is right. electrons are in orbits just like planets. The electron is attracted to the positive charge in the center, as planets are attracted by the gravity of the sun. Their speed keeps them from falling inward to the center.
here is a fun site where you can launch electrons into orbit!
http://www.colorado.edu/physics/2000/applets/orbits.html

Answer 7

because electron orbits around nucleus, it cannnot fall in to the nucleus. the circular motion keeps electron from falling into the nucleous. just like earth rotates around sun

Answer 8

The nucleus is tightly packed with protons, which are positively charged and repel the negatively charged electrons. (The nucleus also contains neutrons which carry no charge.)

Answer 9

centrifugal force acts upon it keeping it from falling into the nucleus these electrons are therefore flying at almost two thirds of the speed of light

Answer 10

Because when the elecrons are in the nearest orbital, they are in their lowest possible energy state. They won't spontaneously leave that state to enter any other energy state.