Should electrons as tiny magnets, stick to a permanent magnet if in appropriate conditions? Why shouldn't the magnet collect them like tiny iron dust?I know they repeal each other but should a certain number of them touch the magnet? Is it,for example,possible collect those electrons from silk cloth after rubbing a glass bar? Would that electrons on the silk align their magnetic dipoles with the permanent magnet if we position the magnet close to the silk producing so a weak (fero)magnetic effect?
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The electrons do have an intrinsic magnetic moment due to their spin.
In order for the permanent magnet to exert an attractive force on them, there usually needs to be a magnetic field gradient as in the Stern-Gerlach experiment (sorry for the german link, but here they have the formula for the force right on top). This should be the case for many permanent magnets.
So yes, the electrons could be attracted and in principle, some of the electrons could stick to the magnet.
But please bear in mind, that these forces are really weak due to the fact that the Bohr magneton (from the magnetic dipole 1) is a really small quantity. Any other effects would be considerably stronger. I'm thinking not only of the electric forces, but mainly effects due to temperature, like random movements/ random spin alignment changes. Then additional effects at the surface of the magnet could occur too.
This hopefully helps you to answer some of your questions above.
A separate question is, if the magnetic dipoles would align with the permanent magnet. The answer here is again "in principle yes". For the alignment, a constant magnetic field is sufficient. This effect is used in electron spin spectroscopy. However, the magnetic field needs to be really strong to produce measurable results, again due to the fact that other effects like statistical movements due to temperature destroy the alignment.
There remains the question, if the electrons could be collected after rubbing a glass bar. The glass/ silk effect is called the triboelectric effect, and involves only electric forces, if I'm not mistaking. It is caused by different work functions of different materials. So with this effect, you would "collect" electrons. However, if you want to pick them, you would have to invest at least the same work function again to get them out of the material. So it may not be practical.
