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
SAT Subject Test in Chemistry SAT Subject Test in Chemistry The SAT Subject Test in Chemistry is a one-hour multiple choice test given on chemistry by The College Board. A student chooses whether to take the test depending upon college entrance requirements for the schools in which the student is planning to apply. Until 1994, the SAT Subject Tests were known as Achievement Tests; until January 2005, they were known as SAT IIs; they are still well known by the latter name. This test consists of 85 questions. The first 23 questions numbered 1-23 are 'classification questions'. The next 15 questions, numbered 101-115, are called