EDTA Titration of Water

Michael Marroquin and Meg Dailey

Regulation of body temperature Gives cells their shape Major component of bodily fluids Keeps skin healthy Cannot store water in our bodies

Importance of Drinking Water

Classification ppm

Soft 0-17.1

Slightly Hard 17.1-60

Moderately Hard 60-120

Hard 120-180

Very Hard 180 and above

Hardness of Water

•May help towards dietary needs•Weak inverse relation between water hardness and cardiovascular disease

Determine the hardness of water in samples taken from campus apartments and dorms

Determine which building has the hardest water

Determine which building has the softest water

Determine if bottled water is more soft than samples

Purpose

Prepare EDTA solution by placing 1.8613 grams of EDTA and 8 mL of buffer in a 500 mL flask and diluting to the mark

Prepare a calcium chloride solution by placing 0.5005 grams of CaCO3 and 100 mL of 0.1 M HCl in a beaker and mixing completely

Place 3 mL of calcium chloride solution, 3 mL buffer, and 4 drops of calmagite indicator and titrate with EDTA

Determine molarity of EDTA

Procedure: Standardization of EDTA

Trial mL CaCl2 mL Buffer mL EDTA Molarity

1 3.00 3.00 14.80 0.0103

2 3.00 3.00 14.50 0.0105

3 3.00 3.00 14.60 0.0104

Average: 0.0104

Data: Standardization of EDTA

Obtain water samples from dorms and apartments on campus

Place 25 mL of water, 3 mL of buffer, and 4 drops of calgamite indicator in a 250 mL Erlenmeyer flask

Titrate water with EDTA Repeat until three good trials are obtained Repeat for each dorm and apartment

Procedure: Titration of Water

The Water Bottles

Tyler Run Apartments

Trial mL Buffer mL Water mL EDTA Hardness of Water

1 3.00 25.00 3.00 50.02 ppm

2 3.00 25.00 2.80 46.68 ppm

3 3.00 25.00 2.80 46.68 ppm

4 3.00 25.00 3.00 50.02 ppm

Average: 48.35 ppm

Standard Deviation: 1.93

Data: Titration of WaterDasani Water

Trial mL Buffer mL Water mL EDTA Hardness of Water

1 3.00 25.00 1.20 20.01

2 3.00 25.00 1.10 18.34

3 3.00 25.00 1.20 20.01

4 3.00 25.00 1.10 18.34

Average: 19.18 Standard Deviation: 0.96

Little Run Lodge

Trial mL Buffer mL Water mL EDTA Hardness of Water

1 3.00 25.00 3.20 53.35 ppm

2 3.00 25.00 3.20 53.35 ppm

3 3.00 25.00 3.50 58.35 ppm

4 3.00 25.00 3.10 51.68 ppm

5 3.00 25.00 3.40 56.68 ppm

Average: 54.68 ppm

Standard Deviation: 2.74

Susquehanna Hall

Trial mL Buffer mL Water mL EDTA Hardness of Water

1 3.00 25.00 3.50 58.35 ppm

2 3.00 25.00 3.70 61.69 ppm

3 3.00 25.00 3.40 56.69 ppm

Average: 58.89 ppm

Standard Deviation: 2.55

Spring Garden

Trial mL Buffer mL Water mL EDTA Hardness of Water

1 3.00 25.00 3.50 58.35 ppm

2 3.00 25.00 3.80 63.36 ppm

3 3.00 25.00 3.70 61.69 ppm

4 3.00 25.00 3.50 58.35 ppm

Average: 60.425 ppm

Standard Deviation: 2.51

Beard Hall

Trial mL Buffer mL Water mL EDTA Hardness of Water

1 3.00 25.00 3.10 51.68 ppm

2 3.00 25.00 3.20 53.35 ppm

3 3.00 25.00 3.30 55.02 ppm

4 3.00 25.00 3.30 55.02 ppm

Average: 53.77 ppm

Standard Devation: 1.60

Codorous Hall

Trial mL Buffer mL Water mL EDTA Hardness of Water

1 3.00 25.00 3.00 50.02 ppm

2 3.00 25.00 2.95 49.18 ppm

3 3.00 25.00 3.10 51.68 ppm

4 3.00 25.00 2.90 48.35 ppm

5 3.00 25.00 3.00 50.02 ppm

Average: 49.86 ppm

Standard Deviation: 1.24

Penn Hall

Trial mL Buffer mL Water mL EDTA Hardness of Water

1 3.00 25.00 2.80 46.68 ppm

2 3.00 25.00 2.85 47.52 ppm

3 3.00 25.00 3.00 50.02 ppm

4 3.00 25.00 2.80 46.68 ppm

Average: 47.725 ppm

Standard Deviation: 1.58

Northside Commons

Trial mL Buffer mL Water mL EDTA Hardness of Water

1 3.00 25.00 3.05 50.85

2 3.00 25.00 3.15 52.52

3 3.00 25.00 3.10 51.68

Average 51.68 Standard Deviation: 1.32

Manor South

Trial mL Buffer mL Water mL EDTA Hardness of Water

1 3.00 25.00 2.90 48.35

2 3.00 25.00 2.85 47.52

3 3.00 25.00 2.85 47.52

4 3.00 25.00 2.90 48.35

Average: 47.94 Standard Deviation: 0.48

Manor West

Trial mL Buffer mL Water mL EDTA Hardness of Water

1 3.00 25.00 4.10 68.35

2 3.00 25.00 4.00 66.69

3 3.00 25.00 3.80 63.36

4 3.00 25.00 3.90 65.02

Average: 65.86 Standard Deviation 2.15

Manor North

Trial mL Buffer mL Water mL EDTA Hardness of Water

1 3.00 25.00 3.40 56.69

2 3.00 25.00 3.60 60.02

3 3.00 25.00 3.60 60.02

Average: 58.91 Standard Deviation: 1.92

Manor Northeast

Trial mL Buffer mL Water mL EDTA Hardness of Water

1 3.00 25.00 3.20 53.35

2 3.00 25.00 3.50 58.35

3 3.00 25.00 3.20 53.35

4 3.00 25.00 3.20 53.35

Average: 54.60 Standard Deviation: 2.50

Brockie Commons

Trial mL Buffer mL Water mL EDTA Hardness of Water

1 3.00 25.00 3.30 55.02

2 3.00 25.00 3.30 55.02

3 3.00 25.00 3.40 56.69

Average: 55.58 Standard Deviation: 0.96

Building Average ppm Classification

Dasani Water 19.18 Slightly Hard

Penn Hall 47.73 Slightly Hard

Manor South 48.35 Slightly Hard

Tyler Run Apartments 48.35 Slightly Hard

Codorous Hall 49.86 Slightly Hard

Northside Commons 51.68 Slightly Hard

Beard Hall 53.77 Slightly Hard

Manor Northeast 54.60 Slightly Hard

Little Run Lodge 54.68 Slightly Hard

Brockie Commons 55.58 Slightly Hard

Susquehanna Hall 58.89 Slightly Hard

Manor North 58.91 Slightly Hard

Spring Garden 60.43 Moderately Hard

Manor West 65.86 Moderately Hard

Summary of Data

Example of CalculationsHardness of Water Using Tyler Run Apartments Trial 1:

Average of Hardness of Water Using Tyler Run Apartments:

Standard Deviation of Hardness of Water Using Tyler Run Apartments:

Dasani clearly had the softest water Manor West had the hardest water Drink bottled water Had some bad trials, however, overall

experiment was successful

Conclusion