How does copper and zinc conduct electricity?

Answer 1

All metals (copper included) form crystals that have the valance electrons in a free floating sea. They are not affiliate with any single atom and can move (fairly) freely between associated atoms. Shoving a charge in at one end of a wire therefore allows all the electrons to 'shove-over' and kick one out the other end.

Answer 2

To keep things simple I will start off with conduction itself and what is actually happening before I get into how various materials affect conduction. When we say electricity is conducted, we are actually referring to the movement of charged particles called electrons along a conducting or semi-conducting material. The force that causes the electrons to move is referred to as an electro-motive force (EMF) and is typically an applied electromagnetic field as in a generator at a power plant or a chemical reaction in a battery.

If you think of conduction in this manner, electrons flowing through a material, it is easier to understand why some materials are better than others at carrying these electrons. The electrons are not simply stored in a container somewhere and poured down a wire, but are a part of the atoms that make up the wire (conductor). There is something special about conducting materials that allows the transfer of electrons to neighboring atoms when an EMF is applied. When conducting materials are in a normal (ground) state they have free spaces in their valence band (see molecular orbital theory or valence energy for more).

When an atom has unfilled orbitals in its valence band, electrons can also occupy the conduction band. Electrons in the conduction band can be easily transferred to the conduction band of neighboring atoms. This is how the negatively charged electrons move through a conductor and "electricity" is conducted. In a material that is an insulator such as rubber, the rubber molecules to not have free spaces in their valence orbitals and the conduction bands cannot be occupied.

Answer 3

Zinc is a natural conductor of electricity although it is not commonly found in stores. I recently did an expiriment for my science fair based on the production of energy using scrap metals, and zinc conducted first 52 watts of electricity, then 50, then 41, then 32, then 10 watts. It caused my volt meter to go crazy, leaving me to believe that zinc holds many electrical cells in its skin.