Copper is formed of copper atoms, which are closely clustered together. If observed closely, one could witness the movement of electrons between the atoms of the copper. Each copper atom turns into a positive ion by losing one electron. Thus, copper is a lattice of positive copper ions with the movement of free electrons among them.
Due to movement of electrons freely through the metal, they are also known as conduction electrons. The presence of these conduction electrons makes the copper a good conductor of electricity and heat.
