HNO3-Physical and Chemical properties

Nitric acid is an inorganic compound with the formula HNO3. It is a highly corrosive mineral acid.The compound is colorless, but samples tend to acquire a yellow cast over time due to decomposition into oxides of nitrogen. Sinno industry available nitric acid has a concentration of 68% & 60% in water.

Nitric acid is the primary reagent used for nitration – the addition of a nitro group, typically to an organic molecule.  which are still more stable and used as synthetic dyes and medicines (e.g. metronidazole). Nitric acid is also commonly used as a strong oxidizing agent.

Our available nitric acid is an azeotrope with water at a concentration of 68% & 60% HNO3. This solution has a boiling temperature of 120.5 °C (248.9 °F) at 1 atm (100 kPa; 15 psi). It is known as “concentrated nitric acid”. The azeotrope of nitric acid and water is a colourless liquid at room temperature.

Two solid hydrates are known: the monohydrate HNO3·H2O or oxonium nitrate [H3O]+[NO3]− and the trihydrate HNO3·3H2O.An older density scale is occasionally seen, with concentrated nitric acid specified as 42 Baume