pH of Water
Question: Does the pH of tap water change from residential houses compared to the Artesian Well?
Hypothesis: The water in the houses will have a lower pH because the water will have been treated with chemicals to make it neutral, whereas the Artesian Well will be slightly higher since it is untreated..
Materials: Water from two houses, water from the Artesian well, pH tester, bottles, glass.
Procedures:
- Gather materials
- Collect 20 ml of water samples from various sources around Olympia High School, and private homes.
- Set up the pH tester
- Calibrate the pH tester by following the instructions in the box.
- Clean the the tester and pat dry
- Place sample in glass
- Place tester in water sample
- Let stand for 3 minutes
- Record the pH measurement that is displayed on the tester
- Reset the tester for each test by washing with water and drying pat dry and pouring out the sample.
- Repeat steps 5-11 for each sample doing three tests for each location
- Analyze the data for any patterns
Controlled Variables: Amount of water, pH sensor, storage of water.
Independent Variables: Location of water sample
Dependent Variables: pH level of water
Data:
House 1 Upstairs
pH test 1: 7.42
pH test 2: 7.32
pH test 3: 7.29
Average: 7.34
House 1 Downstairs
pH test 1: 7.47
pH test 2: 7.47
pH test 3: 7.44
Average: 7.46
House 2
pH test 1: 7.24
pH test 2: 7.19
pH test 3: 7.21
Average: 7.21
Artesian well
pH test 1: 7.93
pH test 2: 7.94
pH test 3: 8.03
Average: 7.96
Results: The pH of water does change from residential houses to the Artesian Well. As evident in the data the houses
Conclusion: My predictions that the pH of the waters would be different was correct. The average pH of the houses were 7.34, 7.46, 7.21 while the average pH of the Artesian well was 7.96, showing that the pH of water is higher at the Artesian well. Another thing to notice is that house 2 had a significantly lower average pH then both tests at house 1. This is expected since the water for the houses is treated to have a neutral pH, while the Artesian well is straight from the ground. These results could be more accurate if more tests were done. Also the pH tester may have been incorrect in its readings because the numbers kept bouncing around and gave some very high readings as well as some low readings.