Indicators change colors at specific pH ranges. Look up the pH for phenolphthalein. Indicators are used knowingly (and sometimes unintentionally) in everyday life.
a) What is the most common indicator used to measure pH of swimming pools? What color changes does it undergo?
b) Red cabbage juice is a common indicator you can make at home. What compounds are responsible for the indicator properties of red cabbage? What are the pH ranges in which it works?
