An acid-base indicator is a substance that changes ... 5 min) Show the students that the HCl solution in the Erlenmeyer is colorless. Add 10 mls of NaOH to the Erlenmeyer and point out the color ...

An acid-base indicator is a substance that changes color as the pH ... indicator and stir so that the water is visibly green. Then add 3-4 drops of 6M HCl and stir until the mixture becomes red. Add 4 ...

A buffer is a solution designed to resist the changes in pH that occur when small amounts of acid or base are added. Buffers must be able ... before filming the guided video for this practice ...