Agricultural grade Purity: 21%min White powder Top manufacturer's supply Ammonium sulphate industrial ... Molecular Weight:132.13,Appearance: white crystals, N: 21% min;Free acid as H2SO4:0.03% max,Moisture:0.3% max,Packing ... ),% ≥21.021.020.5Water content(H2O),% 0.20.31.0Free acid(H2SO4)content,% ≤0.030.050.20Fe content, % ≤0.007 ... As,heavy metal and water insolubles. Ammonium sulphate 21%min white powder