Why does aqueous ch3nh2 turn litmus paper blue
Bases turn red litmus blue. CH3NH2 is a base; therefore, it turns litmus paper blue.
Why is it a base? First it is a base because of definition. By the Bronsted theory it is a base because it accepts a hydrogen ion from H2O. CH3NH2 + H2O ==> CH3NH3^+ + OH^- Second reason when it reacts with water you see it produces a OH^- ion. By the Arrhenius definition the production of an OH^- ion makes it a base.
Aqueous CH3NH2, also known as methylamine, can turn litmus paper blue because it is a basic substance. Litmus paper contains a dye derived from lichens that changes color in response to the acidity or basicity of a solution.
To understand why methylamine turns litmus paper blue, we need to understand the concept of pH. pH is a measure of the acidity or basicity of a solution. A pH value below 7 indicates acidity, while a pH value above 7 indicates basicity.
Methylamine is a weak base, meaning it can accept protons (H+) from water molecules to form hydroxide ions (OH-). When methylamine is dissolved in water, it reacts with water molecules to produce hydroxide ions, which increase the concentration of OH- ions in the solution.
The presence of hydroxide ions makes the solution basic and turns the litmus paper blue. The blue color of litmus paper indicates that the solution is basic or alkaline.
So, in summary, aqueous CH3NH2 turns litmus paper blue because it is a basic substance and when dissolved in water, it produces hydroxide ions that increase the concentration of OH- ions in the solution, making it basic.
The observation that aqueous CH3NH2 turns litmus paper blue can be explained by the basic nature of CH3NH2 (methylamine). Methylamine is a weak base, and when it is dissolved in water, it dissociates to release OH- ions. These OH- ions are responsible for the basic properties of the solution.
Litmus paper is a pH indicator that changes color depending on the acidity or basicity of a solution. Blue litmus paper is typically blue in its neutral form. When it comes into contact with a basic solution, such as one containing CH3NH2, the litmus paper reacts with the OH- ions from the base. This reaction causes the litmus paper to turn blue.