Paper. Cobalt Chloride (Container 100 sheets)
Cobalt Chloride (CoCl2) paper is used for the detection of water leaks or to test for humidity in air. These test papers can quickly and economically measure the presence of relative humidity in the atmosphere. Once the paper is directly exposed to the atmosphere it turns from blue to pink upon contact with relative humidity greater than 2%.
Before testing the blue form is cobalt chloride dihydrate, with two attached water molecules. The compound in the presence of water then gains four extra water molecules to become pink hexahydrate. Heating the paper will reverse the colour change of the reaction.
100 Pieces Cobalt Chloride Paper strips in one pack ( 5 books each with 20 pages).