* N2 (Nitrogen gas): This is a molecule, not an element. It's formed from two nitrogen atoms (N) bonded together.

* O2 (Oxygen gas): Similar to N2, this is also a molecule consisting of two oxygen atoms (O) bonded together.

* Cu (Copper): This is an element. Copper is a pure substance that cannot be broken down into simpler substances by ordinary chemical means.

In summary:

* Elements: Cu (Copper)

* Molecules: N2 (Nitrogen gas), O2 (Oxygen gas)