Kirah Howell, Margaret Walker & Melanie Fannon
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To determine the pH of five water samples
To determine total hardness of these samples
To test for how much sulfate is in the water samples
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Water should have a pH between 6.5 and 8.5
Hard water causes problems to water
Too much sulfate can affect water
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Calibrate pH meter with 4,7 & 10 buffers
Pour 25 mL of water sample into beaker
Test each sample
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Make 2L of 0.005M EDTA solution
Make 200 mL of CaCO3 solution
Standardize EDTA
Combine 3 mL of CaCO3, 5 mL of ammonia buffer,
few drops of calmagite indicator & 25 mL of water
sample into 250 mL Erlenmeyer flask
Titrate with EDTA
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Make BaCl2 solution
Combine 150 mL of water sample , excess of BaCl2
solution and a few drops of concentrated HCl in a 300
mL beaker and boil a hour then cool for 2 days
Filter samples
Titrate with EDTA solution
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Low Molarity of the EDTA
Indicator
Multiple times to find the end point of each
sample.
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pH
Creek
7.72
Little Run
7.82
Business Building
7.70
Campbell Hall
8.12
Country Club
7.78
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[Ca2+] and hardness
Location
Vol (mL) EDTA
Business Building
38.30
Country Club
34.80
Campbell Hall
34.90
Little Run
35.20
Creek
35.03
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[Ca2+] and hardness
Location
[Ca2+]
Hardness (ppm)
Business Building
.00766
306.99748
Country Club
.00696
252.2762133
Campbell Hall
.00698
279.74444
Little Run
.00704
282.14912
Creek
.00674
270.12572
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SO42Location
Vol (mL) EDTA
Business Buidling
86.67*
Country Club
41.10
Campbell Hall
39.53
Little Run
40.73
Creek
41.10
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SO42Location
[SO42-]
Ppm
Business Building*
7.153571016x10-5
6.871791854
Country Club
1.265206813x10-4
12.15370316
Campbell Hall
1.16367316x10-4
11.17836074
Little Run
1.203044439x10-4
11.55656519
Creek
1.16367316x10-4
11.17836074
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The Experiment was successful
The differences of each site
Challenges that were faced
Errors that we encountered
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Belle-Oudry, D. Quantitative Analysis of Sulfate in Water by Indirect
EDTA Titration. Journal of Chemical Education. [Online] September 1,
2008. DOI: 10.1021/ed085p1269.
http://pubs.acs.org/doi/abs/10.1021/ed085p1269 (accessed December 6,
2013)
EPA (Environmental Protection Agency)