* Salts are ionic compounds. They are formed by the electrostatic attraction between positively charged ions (cations) and negatively charged ions (anions).

* Nitrogen dioxide is a covalent compound. It's formed by the sharing of electrons between nitrogen and oxygen atoms, creating a molecule with a neutral charge.

While NO₂ can react with water to form nitric acid (HNO₃), which is an acid, NO₂ itself is not a salt.