Molecular Formula: NaOH; GR (AR) grade; CAS No.: 1310‐73‐2; Purity: min. 97.0%; Solubility in water: to past test; Chloride (Cl): max. 0.01%; Phosphate (PO4): max.0.001% ; Lead (Pb): max. 5ppm; Arsenic (As): max. 1ppm; Silicate (as Sio2):max 0.01%;Sulfate (S04):max0.005%; Nitrogen compounds(as N): max0.001%; Potassium (K):max0.05%; Magnesium (Mg): max.5ppm; Calcium(Ca):max0.002%; Zinc(Zn): max0.001%; Aluminium (AI): max0.002%; Iron (Fe):max5ppm; Nickel (Ni):max.0.001%; Sodium carbonate (Na2C03): max1.0%