Metal reactivity questions

1. The metals that reacted the most with the solutions were magnesium strips and zinc strips. The magnesium strip began to look moldy as it became apparent that the metal was dissolving and reacting chemically to both the silver nitrate (in the first well plate spot) and the copper nitrate (in the second spot).
2. Copper reacted with the fewest substances; the only substance that the copper reacted with was the silver nitrate and even then it just turned black and barely any bubbles.
3. We would expect silver metal to not react with any substance in the lab because silver, which is found in long lasting rings and decorations, barely reacts with any substance. Because copper, which is more reactive than silver, barely reacted with any substance in the lab, we deduced that silver would not react.
4. Magnesium, zinc, copper, and silver
5. The outside of the penny is made out of copper because it is less reactive than the zinc core. Had pennies been made out of only zinc they would not only be extremely reactive they would have an odd appearance.
6. A. A better choice for the outside of a penny could be silver because it is less reactive than copper.
1. Silver is not used for the outside of a penny because it would cost more money to make the penny than the penny actually costs.
7. The metal that is most likely to be found in an uncombined, free state in nature is Zinc because it is a very common mineral.
1. The metal that is least likely to be found in a free state is silver because it is very sought after and hard to come by.
8. Yes we found that silver was too expensive to test and eliminated it from our lab and still figured out that it would not be as reactive. 
1. silver was eliminated because of its high price and low reactivity; we were able to guess that silver would not react.