In this lesson, students will write a brief explanation of what a pH indicator does when introduced to various solutions and use red or blue litmus paper and pH paper to determine if a solution is acidic or basic.

Test the pH of things like coffee, spit, and soap to determine whether each is acidic, basic, or neutral. Visualize the relative number of hydroxide ions and hydronium ions in solution. Switch between logarithmic and linear scales. Investigate whether changing the volume or diluting with water affects the pH. Or you can design your own liquid!