* Physical Change: A physical change alters the form or appearance of a substance but does not change its chemical composition.

* Chemical Change: A chemical change results in the formation of new substances with different properties.

When copper conducts electricity:

* Electrons flow: The electrons within the copper atoms are free to move and carry the electrical current.

* No new substances are formed: The copper atoms themselves don't change their identity or composition.

In essence, the copper is simply acting as a medium for the flow of electrons. No new chemical bonds are broken or formed.