... caking High purity 100% water soluble Base fertilizer Ammonium sulphate 21 fertilizertech garde 21%(AS/SOA)Molecular Formula:(NH4)2SO4, Molecular ... ,Appearance: white crystals, N: 21% min;Free acid as H2SO4:0.03% max,Moisture:0.3% max,Packing:50kgs plastic ... ≤0.030.050.20Fe content, % ≤0.007--As content,% ≤0.00005--Heavy metal(Pb)content,% ≤0.005--Water insolubles,% ≤0.01--Note: When ammonium sulphate ...