Swirl and compare the color to your Universal Indicator pH Color Chart. Pour a small amount of the other solution into your indicator solution. Swirl and compare the color to your color chart.

IntroductionAn acid-base indicator is a substance that changes color as the pH of the solution changes. Indicators work because they are weak acids which when in solution, exist in equilibrium with ...

The color of the solution will be similar to the color of the control. Tell students that if the solution turns blue, it has gone from an acid, past neutral, and is now a base. If this happens, try ...

An indicator changes color when it encounters an acid or base. There are many different types of indicators, some that are liquids and others that are concentrated on little strips of "litmus" paper.