Litmus Paper Definition

Chemistry Glossary Definition of Litmus Paper

Litmus paper
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Litmus Paper Definition: ​

Filter paper which has been treated with a natural water-soluble dye obtained from lichens. The resulting piece of paper, called 'litmus paper', can be used as a pH indicator. Blue litmus paper turns red under acidic conditions (pH below 4.5) while red litmus paper turns blue under alkaline conditions (pH above 8.3). Neutral litmus paper is purplish in color.