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
Korean Chemistry Olympiad After the on-line questions, students will take a test about what they have learned while solving the on-line questions. First grade students in high school take this test. The questions are based on basic chemistry. The test can determine how much the students understand basic chemistry. 80 well-ranked students can join the Summer school 1. About one organic chemistry questions appear in the test. All the tests are held in Konkuk University. 80 people who got a good score will join the Summer School 1, which is usually held far away from Seoul. In the school, students learn basic chemistry