Identifying the Amount of Copper in a PennyTracy Dong
AbstractA penny was tested to determine the mass of actual copper that was in the penny. We preparedour penny solution by adding HNO3 concentrate for a reaction and water for color change. Wetook the other copper solutions provided and prepared them in five different test tubes includingdeionized water. From there, we learned how to use a spectrophotometer by calibrating ourdeionized water before measuring the transmittance for the rest of the solutions. After, wecalculated our data and found that our absorbance was increasing while our transmittance wasdecreasing. We plotted our graph and calculated our slope and y-intercept and determined themolarity of our unknown from there. Using our data, we were able to conclude that we had about1.32% of copper in our penny that we tested out of 2.5g.IntroductionIn 1983, Copper pennies were altered to how they were produced due to the change in value.Due to this, these pennies were tested to investigate how much actual copper is these penniesand how much zinc is actually in these pennies. The purpose of this experiment is to determinethe amount of copper and zinc in these pennies utilizing the following apparatus:Absorbance: The theory of absorbance is based on the Beer-Lambert Law where the relationshipis between the light going through the species and its properties.A=EbC: E is the constant that absorbs the species while b is the width of the lightpathway. C is known as the molarity involved in absorbing the species. For alight-absorption sample, there should be a straight line given off. The purpose of thisline is to be able to identify the concentration of that species.