Lesson 1: Testing pH

pH is the measure of the hydrogen ion concentration. Water is neutral and has a pH of 7. A solution with a pH lower than 7 is acidic, like a lemon, and a solution with a pH higher than 7 is basic, like soapy water. If pool water is at an incorrect pH, it can cause eye stinging and itchy skin. Can you help the swimmers and test the pH to make sure the pH levels are ideal?

Doing the science

1. Start the Pool Bacteria Simulation by clicking on the "Sim" tab.
2. Click on the "pH" checkbox on the section labeled "Tests" and adjust the "Number of Swimmers" to 5.
3. Click on the "Run" button.
4. Click on 0, 6, and 12 under "Time (hours)" to find the pH at each time period. Record the pH in Table 1 below.
5. Hover over the children in the pool and record their comments in the table.
6. Click on the "Reset" button.
7. Repeat steps 2-6 with the number of swimmers designated in Table 1.