Explanatory notes
… (A) SULPHURIC ACID Sulphuric acid (H 2 SO 4 ) is mainly obtained by passing oxygen and sulphur dioxide over a … (platinum, ferric oxide, vanadium pentoxide, etc.). It is freed from impurities (nitrogen compounds, arsenical or … acid contains between 77 and 100 % H 2 SO 4 . It is presented in containers or carboys of glass, in steel drums, …