What Is The Chemistry Of Natural Waters Lab Report

The procedure for this experiment is found in Stephen Thompson’s PSU Chemtrek on p. 10-15 through 10-22 under the “Chemistry of Natural Waters” lab. For the testing, four tap water samples were obtained from Virginia and State College, Pennsylvania—McDonald’s, the Atherton Hotel, and McKee Hall. Each member of the group proceeded through the testing methods in order to determine the hardness for a particular water sample. In accordance with the procedure, the AA technique was used first. Because the water sample from McKee Hall had no suspended particles, no filtration was required prior to testing; however, the sample was diluted with a 1:1 ratio. From the AA spectrometer’s readings (conducted by Dr. Stephanie Le Clair), the absorbance was calculated for the Ca2+ and Mg2+ which were dissolved in the sample connected to the spectrometer through a tube. Following testing, graphs of light absorbance versus metal ion concentration were created, and the obtained equations from the trend line were used to translate the values into the corresponding concentration of CaCO3 (see

For this titration, one drop of EBT indicator, NH4Cl buffer, and the water sample were added to each well in a 1x12 well strip. Once each well was filled, the titration proceeded: one drop of the 2 x 10-4 M EDTA was added to the first well, two drops to the second, three drops to the third, etc. Once one of the wells turned a blue color, that particular well represented the point at which there was excess EDTA and all of the Mg2+ combined with the EDTA to remove the ions from solution and form the chelate. Following the test, the equation MEDTAVEDTA=MCa2+VCa2+ was used to calculate the Ca2+ and Mg2+ concentrations.1 Similar to the previous AA test, the water sample was diluted with a 1:1 ratio along with the Atherton and Virginia samples. The College Avenue McDonald’s sample was diluted with a 1:4 ratio due to its extreme