If an isolated conductor has a net zero charge and is not in an external field, would the free charges still move to the surface of the conductor eg. a conducting sphere? Wouldn't this create an electric field inside the conductor pointing radially outwards as there would be positive ions within the conductor and negative charges on the surface? And then wouldn't the electrons move back to join the positive ions?
[I understand how free charges will move in a conductor to cancel any external field, cancelling the external field inside the conductor, but then wouldn't there still be a field pointing radially outwards?]
I also don't understand this in terms of energy - why is it a lower electric potential energy position for the charges to go to the surface - wouldn't it be lower energy for the electrons to go back to the positive ions?
Gauss's law talks about there being no charges inside a conductor, but wouldn't there still be all the positive ions left there if the conduction electrons have gone to the surface?
My guess is that people are usually talking about any NET charge going to the surface of a conductor. But wouldn't an isolated conductor at equilibrium (as in the general textbook questions on this) be net neutral and so then not have charge on the surface?