Hi, I'm really confused with how electrons become 'free' in a metal. I have a few questions and would be very grateful if someone could shed some light on them. 1. Are the electrons actually free? In a sense that the atom it is attached would essentially become an ion 2. If you take a copper wire which is made up of copper atoms then each atom has 29 electrons, so is it one of these 29 electrons in the outer shell that is free? 3. What is it about metals that enables it to have these free electrons compared with say an insulator?