Replacement Reactions Lab

Conclusion Questions:

Part I

1. What type of chemical reaction occurred?
     Single Replacement

2. What is the solid formed in the reaction?'
     Copper Nitrate

3. Would the reaction still occur if we used aluminum wire instead of copper? Why or Why not?

     Yes, because it would still be the same type of reaction that would occur.

Part II

4. Which of the metals reacted the fastest? The slowest?
     Magnesium was the fastest reaction and tin was the slowest.

5. Based on your observations, rank the metals, including copper, from most active to least. Does this agree with the activity series chart on your reference tables?
     Most active --> least active: Magnesium, Aluminum, Zinc, Tin, Copper


Part III

6. Why did you have to expose the inside of your penny by filing it?
     Filing the edges was the only way to expose the zinc inside of the penny to the HCl.

7. Calculate the percentage of copper in your penny:
     19.7% ≈ 20%

8. Find the percent error in the amount of copper you calculated for your penny, using the known percent of copper you looked up in the pre-lab.
     17.2% ≈ 17%

9. Where might any error have come from, aside from human or instrument error? Be specific.
     We may not have let the penny sit long enough in the HCl (Hydrochloric Acid) to let the zinc fully dissolve away, which left some behind, causing the greater percentage of copper.



10. When acid is added to the penny, bubbles appear. According to your balanced equation, what type of gas do you think is released from the reaction?
     Hydrogen gas is released through the bubbles.