Alchemy-Gold Penny Lab

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Alchemy Lab Day 1
Name:
Introduction:
Date:
Pd:
Alchemists were the earliest forms of chemists, who came about back in the middle ages. They were people who were
attempting to turn various substances into gold. Today we are going to become alchemists, and attempt to turn copper
pennies into gold!
Over the course of this experiment, follow the procedure EXACTLY, and record any observations you can. The more you
record, the better you’ll be set up to get a high grade at the end of this unit.
SAFETY PRECAUTIONS:
These are caustic and dangerous chemicals. As such, only one student will handle the beaker and solution, and will be
wearing gloves at all times. All students will be wearing lab aprons and goggles OVER THEIR EYES at all times, or will be
removed from the lab.
Do Now/Pre-Lab 15 points
1. What is an alchemist?
2. Why should you record ALL of your observations for this lab?
3. How will we stay safe during this lab?
Materials
250 mL Beaker
3.5 g of Zn powder
1 clean penny dated before 1982
60 mL Solution Tongs
Hot Plate
Masking Tape
1
Procedure Part 1:
1. Obtain a beaker, and label it with masking tape with your period number and initials.
2. Carefully pour 30 mL of the clear sodium chloride solution into the 250 mL beaker and place a watch
glass on it. BE CAREFUL. Sodium Chloride is very caustic, it damages skin. If you get some on your skin
rinse it with water immediately!
3. Measure 3.5 g of the zinc powder and add it into the beaker CAREFULLY. Be sure to place the watch
glass back on it when done.
4. Return to your lab station, and put the beaker on the hot plate on medium heat.
5. Wait until you can see steam forming above the solution, but to not let the solution boil.
6. Turn down the heat to level 3.
7. Carefully add the penny and leave in the solution for 10 minutes.
8. After 15 minutes, remove the beaker from the hot plate using a tongs, and set aside.
9. Leave the penny in the solution on the side of your lab area.
OBSERVATIONS: 50 points
Before
During
After
2
REMEMBER: Record observations before, during, and after the
experiment. The more the better!
Procedure Part 2:
1. Light the burner using the button on the handle, and check with the teacher to
make sure that the flame is at an appropriate level
2. While wearing gloves, very carefully remove the penny from the solution (the
silvery layer can be removed by excessive rubbing).
3. Rinse out your beaker and fill it ¾ full with room temperature water.
4. Put the penny in tongs holding only the outside of the penny, and hold it just
above the flame of the burner as shown.
5. Heat the penny until it begins to change color (this takes very little time).
6. Without removing the penny from the clamp, dip the penny into room
temperature water, and place on a paper towel to dry.
OBSERVATIONS:
Before
During
After
3
Read the article via the link on Google classroom to answer the following.
Analysis Questions:
35 points
Read the article Zinc Made More Cents and answer the questions that follow.
1. What happened to the penny in 1982?
a. Why?
2. What was the chemical makeup of pre-1982 pennies?
3. What is the chemical makeup of current pennies?
4. What can happen when a coin’s material value becomes greater than its face value?
5. How much money could the US save by changing the pennies in 1982?
6. In light of this information, how much is a penny of today worth?
4
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