Revision on science assignment

October 27, 2014

Introduction

The experiments in this section were conducted with several objectives in mind. The first experiment on groundwater communication was supposed to show the various possible contaminants can affect water. This was bases on an understanding that ground water is perhaps the most prone to contamination since no artificial methods of purification have been used on it. The successful completion of experiment one for instance would reveal what qualities of a contaminant make it dangerous if it comes into contact with water. It therefore becomes easier for any person to tell where water from a particular source is likely to be contaminated.

Another reason for carrying out the experiments was to determine the real value that a person gets from purchasing bottled water. There has existed a debate on whether bottling of such water is as a result of consumerism or a genuine purpose to provide something other unique. The experiment therefore set to compare the difference in components of tap water and bottles water. The final experiment on filtration was motivated by a need to understand what goes on in a water treatment plant. Perhaps an understanding of the process could lead to the development of a similar but easier water treatment method that can be applied in homes that have no access to clean and treated water (Pan et al., 2012).

Past experiments have tried to compare the content of tap water with bottled water, relying mostly on secondary information. This involves going to the water supplying company and requesting a report on the chemical components in the water and their quantities. The bottling company is also requested to give a similar report. However, this can be time consuming and unreliable because both parties may lie for public relations reasons.

The hypothesis for the first experiment is that the solubility of materials is a major determinant of the ability to contaminate water. In the second experiment, the hypothesis is that sand, charcoal, and gravel can act as suitable filters for water, in almost a similar way to what happens in water filtration plants. The third experiment tests the hypothesis that there is a difference in the chemical composition of tap water and ground water (Pan et al., 2012).

Materials and Methodology

The first experiment made use of clean water and other materials such as vinegar, soapy water, and oil. Water was put into beakers and each of the contaminants added in small bits and students were expected to make observations through site and smell. The aim was to determine which of the substances had the ability to contaminate clean drinking water. The second experiment involved taking a soda bottle and cutting off the bottom and securing the top so that the contents could not escape. The bottle was place upside down and placing charcoal, sand, and gravel, in that order, into the bottle. Muddy water was then added and allowed to settle as students were required to observe and record the cleansing process that followed (Cepeda & Cepeda, 2005).

The third experiment involved placing tap water, Dasani bottled water, and Fiji bottled water, into several labeled beakers. Several tests followed on the various beakers whereby alkalinity was tested as well as the hardness of the water. The pH of the water was determined using a Universal indicator and the readings taken using the normal pH scale in the lab. There were tests for ions such as iron and phosphate, all for sake of determining the chemical components difference between the various waters.

Results

For the first experiment, substances that were immiscible with water were found not to carry any risk of contaminating water while those that could mix with water ended up contaminating it. In the second experiment, gravel, sand and charcoal proved to be good filters of water. They themselves could not contaminate the water because they are insoluble. Gravel filters off large particles of impurities while charcoal filters the finest particles of impurities. The third experiment showed little chemical difference between the composition of tap water and bottled water. It is therefore possible to conclude that perhaps water bottling companies use the same filtration process as water treatment plans do.

Discussion

These experiments show that it is quite easy for a person to evaluate the cleanliness of groundwater based on where it is and the contaminants that are likely to be around it. It is also possible to use simple methods of filtration to cleanse dirty water for domestic purposes, other than drinking and cooking. The reason for the caveat in the last statement is because simple filtration may not be able to rid water off small micro-organisms such as bacteria. Lastly, the third experiment showed that the reason for the continued existence of water bottling companies is not the chemical component superiority of bottled water but rather the convenience it brings. For instance, institutions such as the army are better off buying bottled water than setting up water treatment facilities when working in areas where pure water in not readily available (Cepeda & Cepeda, 2005).

Conclusion

It is evident to see that modern filtration methods are drawn from nature. Groundwater, which appears clean in places such as wells has gone through the filtration process where dirt particles are absorbed by sand and gravel. The other important point to make is that perhaps people need to base their decisions on the preference between tap and filtered water on convenience as opposed to the purity or components of either of them.

References

Cepeda, Z., & Cepeda, E. (2005). Application of generalized linear models to data analysis in drinking water treatment. Revista Colombiana de Estadistica, 28(2), 233-242.

Cerretti, J. K. . . (2009)The Softening of Hard Water and Complexometric Titrations. An Undergraduate Experiment." Journal of chemical education 76, no. 10:1420.

Pan, J., Zhang, H., Li, W., & Ke, F. (2012). Full-Scale Experiment on Domestic Wastewater Treatment by Combining Artificial Aeration Vertical-and Horizontal-Flow Constructed Wetlands System. Water, Air, & Soil Pollution, 223(9), 5673-5683.

Walsh, M. E., Lake, C. B., & Gagnon, G. A. (2008). Strategic pathways for the sustainable management of water treatment plant residuals. Journal of Environmental Engineering and Science, 7(1), 45-52.