Chapter 16.2, Problem 6RQ

Interpretation Introduction

Interpretation: Color of phenol red in acidic solution has to be determined.

Concept introduction: An acid-base indicator or $pH$ indicator change its color over a range of pH when added to a solution containing acid and base. A visible change can be seen even after adding a small amount of indicator in solution.

Some indicators change between colored and colorless states while other change from one color to another color. $pH$ indicators are usually weak acids or weak bases.

Answer to Problem 6RQ

Color of the solution turns yellow.

Explanation of Solution

Phenol red is a  pH  indicator which can quickly indicate the solution is acidic or basic.

When phenol red added to an acidic solution color changes to yellow.

  

Conclusion

Color of the solution turns yellow.