Cobalt Chloride Indicator Paper / Relative Humidity
Cobalt Chloride indicator paper. The vial contains 60 strips @ 8 mm x 55 mm.
Indicates relative humidity or moisture content with a color change.
Pink indicates high humidity while blue indicates low humidity.
Anhydrous cobalt (II) chloride (CoCl2) is blue. When this molecule reacts with water it forms the hydrated chloride (CoCl2. 2H2O) which is purple and then the hexahydrate form (CoCl2. 6H2O) which is pink.