EVERYDAY SCIENCE

Detailed explanation-1: -Expert-Verified Answer. Blue litmus paper turns red in the presence of an acid. Therefore, it can be assumed that the substance in the beaker is an acid. Acids have a pH level of less than 7.

Detailed explanation-2: -Red litmus paper turns blue when placed in a base. Blue litmus paper stays blue when placed in an acid.

Detailed explanation-3: -If the material is basic or alkaline, the red litmus paper turns blue. In acidic solutions, litmus turns red, while in simple solutions, it turns blue.

Detailed explanation-4: -Usually litmus paper is most commonly used to determine the pH of liquids, but one can use it to determine the pH of gases but only under the condition if the paper is dampened with distilled water before being exposed to the gas. Blue litmus paper when not changed to red indicates the solution is basic.

Detailed explanation-5: -The main use of litmus is to test whether a solution is acidic or basic, as blue litmus paper turns red under acidic conditions, and red litmus paper turns blue under basic or alkaline conditions, with the color change occurring over the pH range 4.5–8.3 at 25 °C (77 °F). Neutral litmus paper is purple.