Litmus paper red • Quick and easy determination of acidic and alkaline reaction • changes colour from red to blue when conditions change from acidic to alkaline. Recommended application: • General test for acidic or alkaline reaction: It serves in neutralisation reactions to check whether the change from acid to alkaline or vice versa has taken place. • Litmus paper is the bestknown indicator paper. Chemistry: • Litmus is not a single, chemically defined substance but a natural product containing a mixture of substances. • It is extracted from lichen and probably represents the oldest known indicator dye. • Booklet of 100 strips, 10 x 70 mm • pH range 5,0 - 8,0 • minimum purchase: 5 booklets