... 98.0 pct min 2) Water insoluble: 0.05, 0.1 pct max 3) Iron: 0.001, --- pct max ... 4) ... Molecular formula: Mg(NO3)2.6H2OMolecular weight: 256.40Physicochemical properties: Magnesium nitrate hexahydrate ... organic chemicals.Major indexes of technical and agricultural grade:1) [Mg(NO3)2·6H2O]: 98.0, 98.0 pct ... min2) Water insoluble: 0.05, 0.1 pct max 3) Iron: 0.001, --- pct max ...