Question

What is the effect of potassium hydroxide solution on litmus paper?

• A. Blue litmus to light blue.
• B. Blue litmus to red.
• C. Red litmus to light pink
• D. Red litmus to blue.

Answer 1

The correct option is D

Red litmus to blue.

Litmus paper is an indicator which is used to test if a substance is acidic or basic in nature. Acid turns blue litmus paper red and base turns red litmus paper blue.
Potassium hydroxide $\left(\text{KOH}\right)$ is a base. Therefore, it turns red litmus paper blue.