Appearance: white crystal
Assay: 98% min.
Loss on drying: 0.5% Max.
Chloride: 0.1%ppm Max
Na⁺: 100ppm
SO₄^2- : 50ppm
Other metal ion: 1ppm Max.

Soluble: heating and solve in water or 0.1M NaOH, solution is colorless without residue