pH:4.5-6.0 (5% solution at 25°C)Solubility:190g in 100ml water at 20°CMelting Point:~169ºCInsoluble Material:≤0.005%Residue On Ignition: ≤0.01%Heavy Metals (as Pb):≤0.0005%Chloride (Cl-):≤0.0005% Nitrite (NO2-):To pass test Phosphate (PO43-):≤0.0005%Sulfate (SO42-):≤0.002%Iron (Fe):≤0.0002%Storage and Stability:May be stored at RT Stable for 12 months after receipt. Warnings: Irritant! Oxidizer!Meets or exceeds ACS specifications