RXSOL brand highly purified and well balanced Barium Chloride 10% solution chemically plays role during Sulfate Test, to pricipitate as Barium Sulfate crystal of uniform size.  Other Higher Concentration Product ::: Barium Chloride saturated Solution Testing method of sulfite with barium chloride is based on the precipitation of sulfate ion in a hydrochloric acid medium with barium chloride in such a manner as to form barium sulfate crystals of uniform size.  The glycerol sulfate solution is used to maintain proper crystal size, and control of the stirring and waiting times is necessary to obtain reproducible result.  The resultant turbidity is measured at a wavelength sensitive to turbidity on a photometer.  The blank serves to partially cancel out interferences due to color and suspended matter.    Click here for Testing Procedure  ::: rxmarine.com/SULFATE-TEST-KIT