What color will red litmus paper turn if NH3 is present?

What color will red litmus paper turn if NH3 is present?

• A. Blue
• B. Green
• C. Red
• D. Yellow

Answer: (A)

When red litmus paper is exposed to a basic solution, it turns blue due to the presence of hydroxide ions that increase the pH of the solution. Ammonia (NH3) is a weak base, and when it dissolves in water, it forms ammonium hydroxide (NH4OH), which increases the pH level of the solution. This basic nature of ammonia causes the red litmus paper to undergo a color change from red to blue, indicating the basicity of the environment. The change in color is specifically due to the pH level shifting into the alkaline range, which is characteristic of basic substances. Understanding this chemical behavior is vital in various applications, including laboratory settings and industrial processes, where monitoring pH levels is important.

When red litmus paper is exposed to a basic solution, it turns blue due to the presence of hydroxide ions that increase the pH of the solution. Ammonia (NH3) is a weak base, and when it dissolves in water, it forms ammonium hydroxide (NH4OH), which increases the pH level of the solution. This basic nature of ammonia causes the red litmus paper to undergo a color change from red to blue, indicating the basicity of the environment.

The change in color is specifically due to the pH level shifting into the alkaline range, which is characteristic of basic substances. Understanding this chemical behavior is vital in various applications, including laboratory settings and industrial processes, where monitoring pH levels is important.