Litmus paper helps in the identification of nature of a solution. Litmus paper checks the acidity, basicity and neutrality of a solution. When a litmus paper tums from blue to red when it is dipped in an acid. Similarly, when a litmus paper dipped in a base solution, it turns from red to blue. A neutral solution does not affect the color of a litmus paper. If the red litmus paper does not change color on adding a solution, it indicates that the solution is an acid or a neutral. Moreover, if a blue litmus paper does not change color on adding a solution, it shows that the solution is a base or neutral.