Here's why:

* Na₂HPO₄ is the chemical formula for sodium hydrogen phosphate.

* The subscript '2' after Na indicates there are two sodium (Na) atoms.

* The subscript '4' after O indicates there are four oxygen (O) atoms.

* The 'H' in the formula stands for a single hydrogen (H) atom.

* The 'P' stands for one phosphorus (P) atom.