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occurred after 10 minutes. 15mL of distilled water was added to the copper solution, which indicated a color change. 25mL of concentrated ammonium hydroxide was added in 8mL increments to the nitric acid solution. A zinc hydroxide precipitate was formed after added the first 10 mL, but then redissolved after adding the remaining ammonium hydroxide. An additional 15mL of ammonium hydroxide was added to the nitric acid solution to fully dissolve all the remaining precipitate. The solution cooled to room temperature. The copper(II) tetraamonia complex was then transferred to a 100mL volumetric flask and diluted with water so that the total volume in the flask was 100mL. The flask was inverted consistently for 30 seconds to fully mix the solution and then was labeled as the “penny solution”. Using a spectrophotometer, the absorbance of the “penny solution” was measured at 620nm and was recorded. Part 2: 15mL of .04M of [Cu(NH3)4]SO4was added to beaker labeled “beaker 1”. Using a volumetric pipet, 10mL of distilled water was added into each of the beakers labeled 2-5. Using a volumetric pipet, 10mL of the stock solution was added into beaker 2 (1/2 the concentration of stock solution), 10mL of the solution from beaker 2 was transferred into beaker 3 (1/4 the concentration of the stock solution), 10mL of solution from beaker 3 was transferred into beaker 4 (1/8 the concentration of the stock solution), 10mL of solution from beaker 4 was
transferred into beaker 5 (1/16 the concentration of the stock solution). The absorbencies of each were measured and recorded using a spectrophotometer. Results and Discussion*All data was collected from Nicole Tseng because my partner and I accidentally diluted the penny solution instead of the standard. Dr. Kinsland approved this.