I am not sure I quite understand the distinction between the valence and conduction bands in metals. The simple model we learned in Intro to Chemistry explained that electrons in the metals were delocalized and were shared between all the metal atoms in the metallic crystal. I am not sure if I correctly understand the band model, so correct me if I say something incorrect. According to the band model, the electrons are confined to specific molecular orbitals in between to atoms when in the valence band. If energy is provided then the electrons can occupy higher energy level molecular orbitals in the conduction band. Usually these are the anti-bonding orbitals. So my questions are the following: • Aren't the higher energy level molecular orbitals still between just two atoms? How then can the electrons be shared between all the metal atoms? • Conductivity is supposed to decrease with increasing temperature. Doesn't this contradict with the idea that adding energy will allow the electrons to escape to higher energy levels? • What exactly does it mean when we say the electrons are delocalized in the conduction bands? Are they still confined to the atoms of the solid? They cannot just escape into a vacuum correct?