what is the original color of Phenolphthalein solution? pink or colourless?
The original colour of phenolphthalein is light pink
Phenolphthalein is a pH indicator that undergoes a color change depending on the acidity or alkalinity of a solution. In its pure form, phenolphthalein is actually colorless, but it turns pink or magenta depending on the pH of the solution.
To verify this, you can perform a simple experiment:
1. Obtain a small amount of phenolphthalein solution.
2. Take a clean and empty container, such as a test tube or a small glass.
3. Add a few drops of the phenolphthalein solution to the container, enough to cover the bottom.
4. Observe the solution and you will see that it appears colorless.
5. Now, add some drops of a basic solution, such as sodium hydroxide (NaOH) or soap solution, to the container.
6. As soon as the basic solution comes in contact with phenolphthalein, you will notice that it turns a vibrant pink or magenta color.
7. This color change occurs because phenolphthalein is an acid-base indicator that changes color in alkaline (basic) conditions.
So, in summary, phenolphthalein is originally colorless, but it changes to pink in the presence of a base.