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
Trinder spot test 1992, and of norfloxacin in 1993, in each case using a solution of iron(III) in suplphuric acid. It has also been used for the determination of the presence of bromazepan in 1992, using an iron(II) solution in a hydrochloric acid rather than an iron(III) solution. Trinder spot test The Trinder spot test is a diagnostic test used in medicine to determine exposure to salicylates, particularly to salicylic acid. The test employs the Trinder reagent (a.k.a. Trinder solution) which is mixed with a patient's urine. The colour change, resulting from the Trinder reaction, is immediate, enabling rapid bedside assessment. The Trinder