Indicators are important tools for showing how acids and bases react. They help students see changes in pH, which is a measure of how acidic or basic a solution is. This is especially useful in classes that focus on the Brønsted-Lowry theory.

Here are some key points about indicators:

1. Color Change with pH:

   • Indicators are picked based on certain pH ranges.
   • Many indicators change color when the pH crosses a certain point.
   • For example, phenolphthalein goes from clear to pink when the pH is between 8.2 and 10.
   • Another example is bromothymol blue, which changes from yellow at pH 6.0 to blue at pH 7.6.

2. Showing Neutralization Reactions:

   • In neutralization reactions, an acid combines with a base to create water and salt.
   • Indicators help show the end of these reactions, known as titrations.
   • For example, when using hydrochloric acid (HCl) and sodium hydroxide (NaOH), phenolphthalein changes color to indicate that the reaction is complete when the pH is about 7.

3. Improving Understanding:

   • Research shows that using visual indicators can help students understand better, with some studies showing a 30% increase in understanding.
   • This shows just how helpful these tools can be in teaching and learning.