The purpose of this experiment was to discover the chemical properties that copper has when reacting with other chemicals and how it changes physically during these processes. (Department of Chemistry, 2013) This was achieved through many types of reactions, such as a redox reaction, double displacement, decomposition reaction and single displacement depending on the chemical properties in relation to copper of the other substances when it was added with copper. Copper was either in an aqueous state or a solid state as a precipitate. Another reason why this experiment was performed was to find out whether the initial mass of copper will equal the amount of copper recovered, while learning how to perform the different types of techniques common within a laboratory. (Department of Chemistry, 2013) This was achieved through the quantitative measurement of mass of the initial copper, which was 1.4470g, and the final mass of the copper recovered, 2.6016g, using an analytical balance. Throughout the experiment processes such as heating, mixing, and filtration were used. For the final procedure when the copper compound was isolated into solid copper again the experimental percent yield for the experiment was 179.8% which is nearly double the amount of the initial mass. This did not match with the theoretical yield which is 100.0%.
According to the theoretical calculations this high percentage yield is wrong, and that there is something that is contaminating the copper solid. The different techniques used during the experiment were not very accurate, so this might explain the different percentage yields. During the heating process that separates the water from the recovered copper solid bumping did happen. Some particles of copper left the total amount, but this does not explain the gain in mass. Another reason for this inaccuracy may be that the water may not have been completely evaporated. To avoid both these errors, stirring constantly will fix the bumping issue and checking the copper solid after heating to ensure it is dry will likely fix the large discrepancy of percentage yields. In conclusion, there was a large discrepancy for the percentage yields, which can be fixed through modifications of the laboratory techniques, but two of the other objectives for this experiment were met.
Sythesis of Copper Compounds
Lab partner: Ananythy Jeyasingham
TA: Saurabh Srivastava
Course: CHEM 120L
Date: Oct. 4, 2013