SPADNS reagent solution for fluoride

Buffer Solution pH 4.00  (Sold as each)

Redox Solution 500ml 220 mV                      Redox Solution 220 mV (± 5mV) Standard acts as a Control or Reference Material, rather than as a Calibration Standard. This is because Redox Oxidation/Reduction (ORP) is an absolute measurement and the sensing electrode does not require calibration. This Standard controls the functionality of the sensing and reference electrode, the analysts technique, environmental conditions and the operation of the measuring meter. This 220 mV Redox (ORP) Standard is accurate to ± 5mV, has guaranteed stability throughout its entire shelf life, even after opening the bottle. The Value of 220 mV quoted refers to the potentials of the platinum electrode v Ag/AgCl reference electrode (3M KCl).   NB: We have various brands of REDOX