Sodium is an element, not a molecule. It exists as individual atoms, symbolized by Na.

Here's why:

* Elements are the simplest pure substances that cannot be broken down into simpler substances by chemical means.

* Molecules are formed when two or more atoms bond together.

Sodium can form ionic compounds with other elements, such as sodium chloride (NaCl), where a sodium atom bonds with a chlorine atom. However, pure sodium itself exists as individual atoms.