... white powder Ammonium sulphate industrial gradeAmmonium sulphate 21%tech garde 21%(AS/SOA)Molecular Formula:(NH4)2SO4, Molecular Weight:132.13, ... Appearance: white crystals, N: 21% min;Free acid as H2SO4:0.03% max,Moisture:0 ... impurityno visible mechanical impurityno visible mechanical impurityN content(dry basis),% ≥21.021.020.5Water content(H2O),% 0.20.31.0Free acid ...