Here's why:

* Transition Elements: These elements are located in the d-block of the periodic table, specifically groups 3 to 12. They are characterized by having partially filled d orbitals in their atoms.

* Sodium: Sodium (Na) is an alkali metal, located in group 1 of the periodic table. It has a single electron in its outermost s orbital.

Therefore, sodium does not fulfill the criteria to be classified as a transition element.