Copper: Medium width rectangular strips; bronze and shiny.
Magnesium: Thin rectangular strip; silver and streaky in texture.
Zinc: Larger square strips; silver and shiny.
Procedure:
Before beginning the procedure, we labeled our well plate with the x-axis as each ionic solution, and the y-axis as each metal. Then, we carefully rubbed each metal with steel wool to make them more reactive. After, we put each metal strip in their designated wells and carefully added 10 drops of each ionic solution to each with a beral pipet. We waited a few minutes and observed the reactions of each metal, as recorded below.
Results: Data Table:
Results: Questions: #1-8, page 143:
1. Which metal reacted with the most solutions?
Although both magnesium and zinc showed reactions with copper nitrate and silver nitrate, magnesium’s reaction with copper nitrate was more apparent than zinc’s.
2. Which metal reacted with the fewest solutions?
Copper reacted with the fewest solutions.
3. Assuming that you did not test silver metal, with which solutions (if any) would you expect silver metal to react? Explain your answer, citing evidence from your data and observations.
Although we didn’t test silver due to its high price, going into the experiment we were aware that silver is a very unreactive metal (the reason why it is used in jewelry). Silver would not have reacted with any of the solutions.
4. List the metals (including silver) in order, placing the most reactive metal first (the one reacting with the most solutions) and the least reactive metal last (the one reacting with the fewest solutions).
Magnesium, zinc, copper, silver.
5. Refer to your “metal activity series” list from Question 4. Write a brief explanation of why the outside surface of a penny is made of copper instead of zinc.
Although silver is the least reactive, less than copper, it is too expensive to use on the outside of a penny. Since copper is also an unreactive metal, it is used on the outside of pennies since it will not corrode over time or melt under standard temperatures due to its high melting point.
6. A) Which of the four metals mentioned in this investigation might be an even better choice than copper for the outside surface of a penny? What observational evidence supports your conclusion?
Silver. Silver is the least reactive out of all of the metals.
B) Why do you think that the particular metal that you identified in Question 6a is not used as the outside surface of a penny?
As previously stated, silver is way too expensive to use to make pennies.
7. Given your new knowledge about the relative chemical activities of these four metals,
A) which metal is most likely to be found in an uncombined, or “free,” (metallic) state in nature?
Silver and copper is most likely to be found in an uncombined, or “free” metallic state in nature because they are the least reactive and seldom combine with other substances. This is why copper is used on the surface of pennies and silver (and gold) are used to make jewelry.
B) which metal is least likely to be found chemically uncombined with other elements?
Since magnesium was the most reactive out of the four metals we tested, it is least likely to be found chemically uncombined with other substances in nature. Magnesium combines with other substances very easily due to its high reactivity.
8. Reconsider your experimental design for this investigation:
A) Would it have been possible to eliminate one or more of the metal-solution combinations and still obtain all the information needed to create chemical activity ratings for the four metals?
Yes, it would have been possible to eliminate two of the metal solution combinations and still obtain all of the information needed to create chemical activity ratings for the four metals.
B) If so, which combination or combinations could have been eliminated? Why?
Due to silver’s high price, we eliminated it from our experiment. Since we knew that silver is an unreactive metal, removing it from the test was not a problem. Since we know that zinc is a reactive metal, the reason it is used as the core and not the surface of the penny, we could have removed it from our experiment as well.
Results: Aggregated Data:
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