A pH or acid-base indicator is a compound that changes color depending on the pH of the substance that is added to it. Acids and bases make pH indicators turn different colors. Two substances that ...

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 ...

BTB should be green in color. Add either a few drops of acid or base to adjust the pH of the BTB. (We used a few drops of 0.2 M Hydrochloric acid to adjust the pH of the BTB.) 4, 8 Nothing - this is ...