The Ricca Chemicals mixed anion standard with a composition of 98.90% water, 0.35% potassium nitrate, 0.31% sodium chloride, 0.28% sodium sulfate anhydrous,<0.1 % potassium nitrite, <0.1% ammonium dihydrogen phosphate, <0.1% sodium bromide, <0.1% sodium fluoride, <0.1% chloroform, is suitable for use in laboratory use only. it can be stored at a temperature of 15 to 30 degree c.<>