Dolores RamirezExperiment #8 – The Copper Cycle: Aqueous Inorganic Reaction TypesDolores RamirezChem 2 Lab 2LoganApril 14, 2013Experiment #8 – The Copper Cycle: Aqueous InorganicReaction Types1. Introduction: The purpose of this lab is interpret a sequence of reactants of copper that form a cycle using observations of changes in chemical and physical properties of the compounds synthesized. We also have to classify aqueous inorganic reactions by the type: redox, acid/base, or precipitation. Then we compose a balanced net ionic equation for each reaction and determine the percent recovery of a sample of copper by carefully employing quantitative laboratory techniques.2. Experimental:a) Materials:18- to 20-gauge copper wire;16 M HNO3; 3 M NaOH; 6 M H2SO4; 30-mesh granular zinc metal; 6 M HCL; methanol; acetone.b) Apparatus:Hotplates or a large drying oven; porcelain evaporating dish; rubber policeman; 250 mL beaker; 10 mL graduated cylinder; 25 mL graduated Cylinder; 50-100 mL graduated cylinder; buret or re-pipetter for HNO3..c) Procedure: 1. Cut a length of pure copper that about 0.5 g. (if bot shiny clean it with steel wool, rinse it with water, and dry tithe tissue).2. Weight it to the nearest milligram and record3. Coil the wire into a float spiral, place it in the bottom of 250-mL beaker, and in fume hood add 4.0mL of concentrated (16M) nitric acid,HNO3. Record your observation while swirling, until copper has dissolved. 4. Heating on a hot plate in the fume hood to about 200-250 degrees Celsius speeds up process. Write a balanced net ionic equation describing this reaction: the products include nitrogen dioxide gas and copper (II) nitrate.5. After the copper has dissolved, add deionized water until the beaker is about half full.6. While stirring the solution with a glass rod, add 30 mL of 3.0 M NaOHto your product mixture from part 1 to form copper (II) hydroxide. Record Observations while gelatinous sky-blue precipitate forms and write a balanced net ionic equation describing this reaction. 17. Stirring gently with a glass rod to prevent “bumping” while heating thesolution to boiling on a hot plate. Record your observations and when the transformation in complete, remove the beaker from the hot plate.8. Continue stirring for a minute or so, and then write the balanced equation describing this reaction while allowing the copper (II) oxide precipitate to settle.9. Decant the supernatant liquid and add about 200 mL of hot deionized water.10. Allow the precipitate to settle again, and then decant once more. Speculate on what is removed by this washing and decantation process.11. Add 15 mL of 6.0 M H2SO4, while stirring. Record your observations and write the balanced net ionic equation describing this reaction, whose products include copper (II) sulfate.12. In the fume hood, add all at once about 2.o g of 30-mesh zinc metal, stirring until the supernatant liquid is colorless. Record your observations and write the balanced net ionic equation describing this reaction, whose products include element copper metal.13. When the evolution of gas has become very slow, decant the supernatant liquid and pour it into the appropriate waste container. (Add 10 mL of 6 M HCL if silver grains of zinc are unreacted while heating the solution).14. When no hydrogen evolution can be detected by eye, decant the supernatant liquid, and transfer the copper to a porcelain dish (use spatula or rubber policeman).15. Wash product with about 5 mL add deionized water, allow it to settle, and decant the wash water. 16. Repeat the washing and decantation at least two more times17. Do the same with about 5 mL of methanol and decant.18. Dispose of the methanol in the proper receptacle.19. Perform two analogous washes similar volumes of acetone, placing therinses into the methanol container.20. Place porcelain dish in hot plate in the fume hood and dry copper. Then weigh to nearest milligram.3. Results and Discussion:All results to this experiment are found on pages 4-5. Most of the results were the weight of the copper recorded at the beginning of the experiment, the observations through each of the parts in the procedure and the unbalanced net ionic equations that were given at the begging of the lab for each of the parts. Part 1 Observation: When 4.0 mL of HNO3 was added it produced a greenish solution and a brown fume that smelled like chlorine. Bubbles formed around the wire. The water added slowly turned the solution from bright green to light blue.2Part 2 Observation: When adding 30 mL of 3.0 M of NaOH the solution became bluish but darker and blue ppt. formed that looks gelatinous. As we boiledit, the solution became thicker turning black.Part 3 Observation: When we isolated copper (II) oxide we first removed the solution from the hot plate and we stopped stirring so the black of the solution would settle down to the bottom of the beaker. We then decant the solution by removing the solution that was left at the top of the blackish substance. The materials being removed are the excess solution is the deionized water and oxygen gas.Part 4 Observation: When adding 15 mL of 6.0 M H2SO4 all ppt. (black substances left at the bottom of the beaker) dissolved and turned sky blue.4. Conclusion:As conclusion this experiment was successful. We were able to successfully interpret a sequence of reactants of copper that form a cycle using observations of changes in chemical and physical properties of the compounds synthesized. We also were able to classify aqueous inorganic reactions by the type: redox, acid/base, or precipitation in doing so, we compose a balanced net ionic equation for each reaction that was balanced. We were able to determine the percent recovery of a sample of copper by carefully employing quantitative laboratory techniques. This was done by dividing the mass recovered of copper by the initial wire mass and multiplying it by 100% thus giving me the % of copper recovered.a) Initialed Duplicate Laboratory Notebook Page(s):i. The initialed duplicate laboratory notebook page(s) must be included after your conclusion upon report submission.5. Report Questions:1) Refer to pages 6-7 for results on balanced equations2) The mole ratio of the reactants of the first reaction is 1:1, but the mole ratio of the reactants for the balanced reaction is 1:4:2.(Work for the moles of Cu and HNO3 found on page 8.)There were 0.00598 moles of Cu in reagents in the balanced reaction and 0.064 moles of HNO3