Water Hardness Lab Report
November 6, 2014
The Chemistry of Natural Waters
Kareem Ali, Dima Alfawaz
Stephanie Le Clair
Introduction Water hardness is a way of defining the quality of water based upon the amount of Ca2+ and Mg2+ions that the sample contains.1 Water mostly becomes hard by flowing over weathering rocks which release these ions into the water. These released ions dissolve in water and then react with various elements, ions and compounds that come into contact with the water, which in some cases can become a nuisance.
When trying to wash your hands or dishes, calcium reacts with soap to form soap scum. This soap scum leaves hard water spots on dishes and leaves an uncomfortable film on your …show more content…
I found that the pond water in the Hammond Park ranked the highest with 432 ppm for the AA concentration and 440 for the EDTA concentration. The second highest hardness was the Shulze Hall tap water which had a concentration of 328 ppm for the AA concentration and 300 ppm for the EDTA concentration. The Aquafina water bottle was significantly softer than the first two samples. It had an AA concentration of 3.58 ppm and an EDTA value of 20.0 ppm. According to a scale measuring the severity of water hardness, both the pond water and tap water were considered very hard. The Aquafina bottle was considered soft when put into this comparison. According to the values, 0-60 ppm is soft, 61-120 ppm is moderately hard, 121-180 ppm is hard and 181+ ppm is considered very hard.10 In my hypothesis, I thought that the tap water would have a higher water hardness because it would pass over more weathering rocks that would pick up extra calcium and magnesium. This portion of my hypothesis was wrong. The hardness of the pond water far surpassed that of the tap water, which shows that there is a decent amount of softening that occurs before the water gets to your faucet. This is backed up by the state college water report. The water is filtered before it becomes tap water which will get rid of some of the polyvalent ions in the pond water.11 The second portion of my hypothesis was that the majority of the softening in the bottling process was from tap water to actually bottling the Aquafina water. The concentration dropped close to 300 ppm in both the AA and EDTA