Turns red litmus to Blue.

Q. ________ turns red litmus to blue.

a.) Acid

b.) Base

c.) Salt

d.) Water

Answer: (b)

Explanation: Base turns red litmus blue.

Know more about litmus:

• Litmus is a water-soluble combination of different colours obtained from lichens. Filter papers are frequently employed in the production of one of the oldest forms of pH indicator, which is used to test materials for acidity.
• cellulose, lichens, and wood-derived auxiliary compounds are the principal raw materials utilised to manufacture litmus paper. Litmus paper is mostly made of paper, as the name implies. Litmus paper must be free of impurities that could cause the pH of the measurement device to fluctuate. Litmus paper, like most paper, is created from wood cellulose.
• Litmus is generally used to determine the acidity or basicity of a solution. Litmus indicator solution turns red for acidic solutions and blue for alkaline solutions. This causes neutral solutions to turn red.
• Red litmus paper and blue litmus paper are two types of litmus paper that are generally more trustworthy. To determine whether a solution is acidic or neutral, litmus paper is employed. Litmus paper does not provide precise acid or base strength information.