Litmus "Lecanora tartarea" (Norway, Sweden), "Variolaria dealbata", "Ochrolechia parella", "Parmotrema tinctorum", and "Parmelia". Currently, the main sources are "Roccella montagnei" (Mozambique) and "Dendrographa leucophoea" (California). The main use of litmus is to test whether a solution is acidic or basic. Wet litmus paper can also be used to test for water-soluble gases that affect acidity or alkalinity; the gas dissolves in the water and the resulting solution colors the litmus paper. For instance, ammonia gas, which is alkaline, turn the red litmus paper blue. Blue litmus paper turns red under acidic conditions and red litmus paper turns blue under basic or
Colorimeter (chemistry) Colorimeter (chemistry) A colorimeter is a device used in colorimetry. In scientific fields the word generally refers to the device that measures the absorbance of particular wavelengths of light by a specific solution. This device is commonly used to determine the concentration of a known solute in a given solution by the application of the Beer-Lambert law, which states that the concentration of a solute is proportional to the absorbance. The essential parts of a colorimeter are: In addition, there may be: There are many commercialized colorimeters as well as open source versions with construction documentation for education and for