The test paper allows the quick and easy detection of water and water vapour. On contact with water the paper changes colour from light blue to dark blue. The reaction is not reversible. Even after drying the contact with water can clearly be proved.
The test paper is used to control the leak tightness of tubing or to detect condensed water. It can also be used to control, if sensitive products like electronics come into contact with water. This helps to detect unjustified complaints. In chemical laboratories the test paper is used to control solvents. If the paper remains uncoloured after evaporation of the solvent, the solvent is anhydrous. In reactions sensitive to water it can then safely be used. For the detection of water vapour in gas streams the paper is moistened with anhydrous isopropanol. The gas stream is directed on the paper. The presence of water vapour is indicated by a blue colour.
|Type:||qualitative test pape|
|Colour reaction:||light blue to dark blue|