It's no myth, just call us Lith: Retrieving Copper Lab

Makena G.

Nina G. 

Nicolette E.

Dr. Forman 

Chemistry

Questions: 

1)

a. Since CuO does not react with HCl, but copper does, by adding 50 mL HCl to our beaker of 0.99 g of what we thought was pure CuO, we were able to see unconverted Cu form at the bottom of the beaker. This means that our original reaction was incomplete.

b. Maybe by exposing more of the original copper to oxygen, a more complete reaction would have occurred and more copper(II) oxide would have formed.

2)

a. Only .71 g reacted when we heated it. 

b. 0.71/0.99 x 100% = 71%

71% of the total copper sample reacted when heated.

3)

a. Zn: + Cu2+ → Zn2+ + Cu:

b.                                                                      

i. Zn was oxidized.

ii. Cu was reduced.

iii. Zn is the reducing agent.

iv. Cu is the oxidizing agent.

4)

a. The color of the solution cleared and the zinc became brick red and broke apart.  

b. This is because since zinc is more reactive than copper, the zinc caused copper to reduce as it oxidized in the solution.

c. Once the color was completely clear, it was an indication that the Cu^2+ ions in the solution had reduced into solid Cu. The zinc had oxidized and became Zn2+ ions in the solution.

5)

a. Cu2+ ions and solid Zn were “used up” in this recovery process.

b. Cu2+ reduced into solid Cu and Zn was oxidized into Zn2+ ions within the solution.

Heating the copperoxide with hydrochloric acid

Zinc reacting with copper

Data Table: 

Histogram: 

There are differences in the data because some groups may have not been able to recover all the copper and some may have lost some copper through some of the steps. Another reason could be that some groups may have not subtracted the weight of the filter paper when they were measuring all the stages.