Copper Cycle
The copper cycle involves many different type of reactions. In this lab you will investigate the various types of reactions that are used to complete the cycle. Solid copper will be added at the beginning of the reactions. Due to the law of conservation of matter the amount of copper put into the reaction should also come out of the reaction at the end.
The reactions that you will perform are generally outlined in the following cycle:

Reactions:
1. 8HNO3 (aq) + 3Cu (s) + O2 (g)  3Cu(NO3)2 (aq) + 4H2O (l) + 2NO2 (g)
2. Cu(NO3)2 (aq) + 2NaOH (aq) 
3. Cu(OH)2 
4. CuO (s) + H2SO4 (aq) 
5. CuSO4 (aq) + Zn (s) 
Materials:
250 mL beaker Aspirator H2O
Glass funnel Rubber tubing 15 mL - 6.0 M Sulfuric Acid
Ring stand Bunsen burner 2.0 g Zinc powder
Ring  0.5 g copper wire 10 mL - 6 M Hydrochloric Acid
Wire Gauze 4.0 mL - 16 M Nitric Acid
Finger clamp 30 mL - 3.0 M NaOH

Set-Up:
1. Create a fume hood from a funnel surgical tubing and aspirator.
2. Support the 250 mL beaker with a ring and wire gauze.
3. Connect the funnel with a finger clamp over the 250 mL beaker.
4. Connect hose to funnel and aspirator (fume hood maybe used in lieu of funnel and aspirator set-up).

Procedures:
1. Mass a 250 ml beaker and record in the data table.
2. Mass out approximately 0.500 grams of no. 16 copper wire and record the mass of the copper in the data table and place the copper in a 250 mL beaker.
3. Acquire 4 to 5 mL of Nitric Acid in a graduated cylinder from your instructor.
4. Start the aspirator and pour the HNO3 into the beaker with the copper. (Caution fumes that are given off in this reaction are poisonous. If some of the acid makes contact with your skin quickly rinse the contaminated area.)
5. Record your observations of the first reaction in detail. (color change, state change, gas evolution, temperature change.)
6. After the reaction add 100 mL of water. Record observations.
7. Add 30 mL of 3.0 M NaoH to the beaker and describe the reaction.
8. Place the beaker back on the ring stand and heat until the solution begins to boil the solution should change to a new color in the heating process. Record your observations. Check with the teacher before moving on.
9. Remove from the heat and let the precipitate settle.
10. Decant and wash with hot water. And decant again.
11. Acquire 15 mL of 6.0 M H2SO4 from your instructor and to the beaker. Record your observations.
12. After the reaction is complete add 2.0 g of Zinc to the solution. Observe and record.
13. Add 5 mL of HCl to the solutions and decant. Wash the solution 3 times.
14. Allow to dry overnight and mass first thing the next day.
Data Table Mass of 250 mL beaker
Mass of copper wire before experiment
Mass of 250 mL beaker and sample after the experiment
Mass of copper after the experiment
% yield
Observations: In the observations use the chemical reactions from the introduction to help explain some of the observed phenomena (may include pictures).
1. Addition of HNO3
2. Addition of 100 mL of water
3. Addition of NaOH
4. Addition of Heat
5. Addition of H2SO4
6. Addition of Zinc
7. Addition of HCl
Data Analysis:
1. Must present (maybe listed) balanced net ionic equations for all reactions that occurred during this lab (total of 5).
2. Calculate % Yield, make sure to show formula.
3. Include error summary based on the percent yield.

Guiding Questions for Conclusion:
1. What reactions were metathesis reactions in the lab?
2. What reactions were oxidation reduction reactions in the lab?
3. What is the difference between metathesis and oxidation reduction reactions?
4. Was the first reaction endothermic or exothermic? Explain your response.
5. Discuss the most difficult part of this lab and why it was difficult.