Question: Will the Ph and Alkalinity of a river change after flowing through an industrial area?
Hypothesis: The pH and Alkalinity will change because of the runoff from the city in general from oil, litter, and possible runoff from the industrial area of Spokane.
Materials: 3 clean containers, pH/Alkalinity strips, and the Test results sheet.
Procedure: 1. Gather materials 2. Collect three 20 ml of water samples before, during, and after river water has flowed through Spokane. (North end of river, City Area, then West end) 3. Label containers 4. For each sample, dip a pH strip test into the 20 ml sample and wait 2 seconds 5. Shake excess water and wait until the tabs change colors, showing results 6. Compare the result colors to the test results sheet to determine levels of pH and Alkalinity, and record. 7. Repeat steps 4-6 three times for each sample of river water 8. Analyze the results of the tests
Controlled Variable: Amount of water, container, pH strips Independent Variable: Location of water sample Dependent Variable: pH and alkalinity of the water sample
Data: A=Alkaline North Test 1:pH-6.5 A-40 Test 2:pH-6.5 A-40 Test 3:pH-6.5 A-40
Mid City Test 1:pH-7 A-40 Test 2:pH-7 A-40 Test 3:pH-7 A-40
West Test 1:pH-7 A-40 Test 2:pH-7 A-40 Test 3:pH-7 A-40
Results: The results showed that the pH very slightly raised after the river reached the city area.
Conclusion: My prediction that the pH would change is correct, however the Alkalinity stayed consistent through the tests. The results could mean that city and industrial pollution is getting into the river. But, there was only a slight difference in the color results between 6.5 and 7 pH, and the perception of the color results could vary from person to person so even with repeated trials pH strips are not completely accurate. A more accurate way of measuring the pH would be to use a digital pH tester because you could have more precise data estimating numbers instead of colors.