Question

Name the source from which litmus solution is obtained. What is the use of this solution ?

Answer 1

Hint: We know that litmus is obtained from a mixture of dyes. Try to figure out the source of these dyes. We know that litmus is used in many chemical reactions. Chemical reactions involving acids and bases use this litmus for identifying equivalence points.

Complete step by step answer:
We know that litmus is an organic compound prepared from a mixture of dyes which are extracted from lichens, cellulose compounds, and some other organic compounds. Impurities are removed from the litmus solution to prepare litmus paper. Litmus preparation requires several varieties of lichens. Cellulose treated with some solvents is used in the preparation of litmus paper. Litmus paper preparation is almost similar to the normal preparation but this litmus paper is infused with lichens.
We use litmus paper to test whether a substance is acidic or basic or neutral. For testing solutions whether it is acid or base, we need two colors of litmus papers. Blue litmus turns to red in the presence of acidic solution. Red litmus turns to blue in the presence of a basic solution. Both litmuses turn to purple in the presence of a neutral solution. Litmus has 2 different structures in acidic and basic solutions.

Note: Litmus paper test is quick but we cannot determine the pH of the solution by this test. We can reuse litmus paper. Litmus paper changes color only when the pH of the solution is in a given range. Otherwise, the nature of the solution cannot be determined.