Copper Transformation Lab Report - Lab-Chem 1425-010 - 2017-18 PDF

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Copper Transformation Lab Report...

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Prelab: 1. Three molecules used in biology that have metal ions in their structure are Copper, Copper (II) Ions, and Cisplatin. Copper molecules are necessary for providing a homeostasis of ion concentration within the body. When Copper is not properly regulated in the body, diseases can occur. Copper (II) Ions can damage DNA and is one of the causes of diseases such as Alzheimer’s disease. Cisplatin is a molecule that prevents DNA replication, ultimately causing cell death. This molecule is helpful to researchers who are trying to find ways to stop cancer. 2. The glassware needed for this experiment are 100 mL beakers, a glass funnel, a watch glass, and a glass rod. Other pieces of equipment needed for this experiment are goggles, filter paper, and balances. During the experiment, observations to make are about the precipitate formed in step 2, how the heat affects the CuO in step 3, how the sulfuric acid affects the Copper in step 4, how the reaction in step 4 affects the Copper, how the Copper dissolves in deionized water in step 6, and finally, observe the transformation from the solution to solid copper in step 7. Measurements needed for this lab will 25 mL of hexaaqua copper (I), 8 mL of 5% sodium hydroxide solution, 20 mL of deionized water, 10 mL of sulfuric acid, 1g of Zn, 1g of copper (II) sulfate pentahydrate, 25 mL of deionized water, and 1g of Zn. Observations/ Meaningful Data Tables/ Meaningful Figures/ OR Analysis/Conclusions 1. Observations a. Step 1: The hexaaquacopper (II) solution was a light turquoise blue while the 5% sodium hydroxide solution was a clear color. b. Step 2: In step 2, 20 drops of 5% hydroxide solution was dropped into the hexaaquacopper (II) solution which formed a dark blue precipitate. After 20 drops of 5% hydroxide solution was dropped into the hexaaqua hydroxide solution, the litmus paper turns blue when a drop of the solution was placed onto the paper. c. Step 3: In step 3, 20 mL of deionized water and two boiling stones were added to the solution formed in step 2. After being heated at 90 degrees Celsius for eight minutes and fifty seconds, the precipitate turned to a dark blue. The precipitate began to form clumps at the bottom of the beaker as well as at the top of the surface. d. Step 4: In step 4, the solid turned into a black and dark blue/ green color. The solid was filtered out into a 50mL beaker with sulfuric acid. The liquid that was filtered out was a light, clear blue. e. Step 5: In step 5, Zinc was added to the blue solution. When the two reacted, they began to fizz. After the Zinc reacted with the solution, the Zinc turned a little red. f. Step 6: In step 6, the copper (II) sulfate pentahydrate was dissolved in 25 mL of deionized water. The deionized water is clear and the copper (II) sulfate pentahydrate was blue and looked like small, ground up rocks. When the copper (II) sulfate pentahydrate was dissolved, it turned into a light blue. g. Step 7: In step 7, When Zinc was added into the blue solution, the Zinc instantly

turned black. Adding the sulfuric acid made the Zinc turn red and fold to the top of the surface. 2. In method 1 of the experiment, we got 0.257g of copper metal and in method 2 of the experiment, we got 0.924g of copper metal. Based on our observations and the data collected, the second method is the better method because we receive a larger yield of copper metal. In method 1, we have to go through five steps in order to make copper metal whereas in method 2, we only have to go through two steps to make copper metal. Less steps means that the chances of error decreases. On a molecular level, the copper metal produced in method 2 has a larger yield than the copper metal produced in method 1. Zinc reduces the copper 2+ ion into a solid copper metal. 3. Observations a. Step 1: The hexaaquacopper (II) solution was a light turquoise blue while the 5% sodium hydroxide solution was a clear color. b. Step 2: In step 2, 20 drops of 5% hydroxide solution was dropped into the hexaaquacopper (II) solution which formed a dark blue precipitate. After 20 drops of 5% hydroxide solution was dropped into the hexaaqua hydroxide solution, the litmus paper turns blue when a drop of the solution was placed onto the paper. The sources of error could be in the amount of drops used and this could affect the yield of copper metal produced at the end of the experiment. c. Step 3: In step 3, 20 mL of deionized water and two boiling stones were added to the solution formed in step 2. After being heated at 90 degrees Celsius for eight minutes and fifty seconds, the precipitate turned to a dark blue. The precipitate began to form clumps at the bottom of the beaker as well as at the top of the surface. The sources of error could be in the amount of time we heated the solution or in the temperature we heated the solution at. d. Step 4: In step 4, the solid turned into a black and dark blue/ green color. The solid was filtered out into a 50mL beaker with sulfuric acid. The liquid that was filtered out was a light, clear blue. The source of error could have been in the filtering process. We could have improperly filtered some of the substance by not filtering it completely. e. Step 5: In step 5, Zinc was added to the blue solution. When the two reacted, they began to fizz. After the Zinc reacted with the solution, the Zinc turned a little red. The source of error in this step could have been an improper reaction. If the blue solution that was made in previous steps was’t made properly, then the reaction with the Zinc would have been affected. f. Step 6: In step 6, the copper (II) sulfate pentahydrate was dissolved in 25 mL of deionized water. The deionized water is clear and the copper (II) sulfate pentahydrate was blue and looked like small, ground up rocks. When the copper (II) sulfate pentahydrate was dissolved, it turned into a light blue. The source of error in this step could have been not dissolving the copper (II) sulfate pentahydrate well enough. g. Step 7: In step 7, When Zinc was added into the blue solution, the Zinc instantly turned black. Adding the sulfuric acid made the Zinc turn red and fold to the top of the surface. The source of error could have been in the blue solution we used.

If the blue solution used was made incorrectly, it would affect the reaction between Zinc and the blue solution. 4. The main difference in method 1 and method 2 was the amount of steps used. In method 1, there were five steps before copper metal was produced whereas in method 2, there were only two steps before copper metal was produced. When there are more steps, there is room for more errors which effects the yield. The yield is the amount of a product obtained in a chemical reaction and in this experiment, method 1 produced a yield of 0.257g while method 2 produced a yield of 0.924g. Method 2 produced more than three times as much copper metal as method 1 did. Method 1 also took much longer to complete than method 2 did. Method 2 is the preferred method to use for many reasons include safety and yield considerations. In method 1, more chemicals and materials are handled. When more chemicals and materials are handled, it increases the chances for an accident which can be unsafe. Regarding the yield, method 2 produces more grams of copper metal than method 1 does. Ultimately, method 2 is the preferred method. According to an article written by OMICS international, you can use a percentage yield and theoretical yield to measure the effectiveness of an experiment. If we wanted to find out the percentage yield in our copper transformation lab, we could use the percentage yield to find it. References:

(1968) Masthead. The Journal of Organic Chemistry 33....