- NH4Fe(SO4)2·12H2O - M = 482,19 g/mol - CAS [7783-83-7] - EINECS-No.: 233-382-4 - Density: 1,025 g/cm3 - Tariff number: 2833 30 00 00 - Applications: analytical chemistry, laboratory reagent, titrant in volumetric analysis. SPECIFICATIONS factor: 0,995 - 1,005 uncertainty ± 0,003 1 ml = 0,04822 g (NH4)Fe(SO4)2 ·12H2O This volumetric solution was checked by means of potentiometric methods using a sodium thiosulfate standard solution, that was also checked against Scharlau's potassium iodate volumetric standard. Scharlau's volumetric standards are directly traceable to the Standard Reference Materials from NIST (National Institute of Standards and Technology, USA).