Indicators are substances that change colour when they are added to acidic or alkaline solutions. Universal indicator is the indicator most commonly used in the laboratory. If universal indicator is ...

An 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 their ...

Note: This video is designed to help the teacher better understand the lesson and is NOT intended to be shown to students. It includes observations and conclusions that students are meant to make on ...