* Neon (Ne) is a noble gas, meaning it has a full outer shell of electrons. This makes it extremely stable and unreactive. It doesn't easily form bonds with other elements.
* Copper (Cu) is a metal, and metals tend to be more reactive than noble gases. They have a tendency to lose electrons and form positive ions. Copper is relatively reactive, though not as reactive as some other metals like sodium or potassium.
In summary: Copper is much more reactive than neon.
