Assay (complexometric): ≥ 99.0 %
Substances insoluble in dilute acetic acid: ≤ 0.02 %
Chloride (Cl): ≤ 0.002 %
Nitrite and Nitrate (as NO₃): ≤ 0.005 %
Total nitrogen (N): ≤ 0.02 %
Ca (Calcium): ≤ 0.01 %
Cd (Cadmium): ≤ 0.002 %
Cu (Copper): ≤ 0.002 %
Fe (Iron): ≤ 0.002 %
K (Potassium): ≤ 0.02 %
Na (Sodium): ≤ 0.05 %
Zn (Zinc): ≤ 0.003 %
corresponds to ACS