How is litmus paper formed by lichen ?
Solution:
Litmus paper is prepared by dipping ordinary or special paper in lichens (mainly Roccella tinctoria) solution and dried which turns red in response to acidic conditions (pH < 7) and blue under alkaline conditions (pH > 7). The strip is produced by treating with a specific indicator - a mixture of 10-15 natural dyes obtained from lichens.
Litmus paper is prepared by dipping ordinary or special paper in lichens (mainly Roccella tinctoria) solution and dried which turns red in response to acidic conditions (pH < 7) and blue under alkaline conditions (pH > 7). The strip is produced by treating with a specific indicator - a mixture of 10-15 natural dyes obtained from lichens.