[DaveD]

Hi,

I am taking a graduate Inorganic chemistry course.  At our first lecture we discussed the hydrogen atom, and we had a discussion about whether or not the electron can be on (ie in physical contact) with the proton.  This seemed strange to me ... if this happened, could the electron have enough energy to overcome the electrostatic attraction and leave the proton?  Once in contact, would any physical change come to either the proton or electron? I've done a little online searching without much luck, trying to find out what happens when an electron and proton come into contact.  The best I've found so far talks about an electron, proton, and neutrino coming together and forming a neutron.  Can anyone lend me some leading references?   Thanks much.

[Yggdrasil]

The answer to this problem relates to the Heisenberg uncertainty principle.

[DaveD]

Thanks for the reply ... as I understand the Heisenberg uncertainty principle, locating a particle in a small region of space (ie, locating and electron on a proton) would result in its momentum (or wavelength in the case of the electron) becoming very uncertain.  So ... if there is a limit to amount uncertaintly possible in the wavelength, then it seems like one could not know the position of an electron in a region as small as a proton.  But I don't know if there is such a limit.

[Yggdrasil]

I guess the point with the Heisenberg uncertainty principle is that, if you can localize the electron to the proton, the uncertainty in its momentum will become large (it will be able to access larger momenta).  This means that it will be able to escape contact with the proton quickly despite the electrostatic attraction between the proton and electron.

[Mitch]

Protons can gobble electrons:
http://en.wikipedia.org/wiki/Electron_capture

but it will definitely not happen with Hydrogen. I always default to the following chemical logic with regards to questions like this. There is this thing called quantization, it prevents electrons from smoothly falling through the coulomb potential and interacting with the proton, some exceptions of course exist.

I can also default to a nuclear logic and look at the mass-energy change for,


Since the mass of a neutron is larger than a proton & electron, then the reaction can not occur without the input of a lot more energy. Hope these two different perspectives help.

[DaveD]

Hi,

I'm back online after a weekend away . yes, thanks again for both replies they do help give me a better perspective on this.