Nitric acid. Computer model of a molecule of nitric acid. This is a strong acid, which means that it is highly dissociated when dissolved in aqueous solution. Acids are chemicals that ionize in water to produce ions of hydrogen. Most metals react with nitric acid to form nitrates and nitrogen oxides. Nitric acid is also a strong oxidizing agent. The molecule's chemical formula is HNO3. The atoms are shown as colour-coded spheres in this ball-and-stick model: hydrogen (gold), nitrogen (blue) and oxygen (red).