AVA Chemicals [P] Ltd. Manufactures Ferric Ammonium Salt of Ethylene Diamine Tetra Acetic Acid. AVA Chemicals [P] Ltd. Is an ISO 9001:2000 certified company. Chemical formula of the Ferric Ammonium Salt of Ethylene Diamine Tetra Acetic Acid is C10H12N2O8 Fe NH4. NH4OH. The molecular weight of the chemical is 397.2. Ferric Ammonium Salt of Ethylene Diamine Tetra Acetic Acid is a red brown clear liquid. Ferric Ammonium Salt of Ethylene Diamine Tetra Acetic Acid measures 7.0 - 8.0 in pH rating scale. The assay of this chemical is minimum 640 grs. Per litres.