We are offering nitric acid • nitric acid, also known as aqua fortis and spirit of niter, is a highly corrosive strong mineral acid. The pure compound is colorless, but older samples tend to acquire a yellow cast due to decomposition into oxides of nitrogen and water. cas number 7697-37-2 formula: hno3 density: 1.51 gcm³ molar mass: 63.01 gmol boiling point: 83 °c iupac id: nitric acid melting point: -42 °c