Making Cents Lab

by Liz LaRosa

www.middleschoolscience.com

Objectives:

• to become proficient in using a balance

• to determine the mass of a penny

• to see if there is a change in mass through the decades

• to learn what metals are used in making pennies

• to determine if the value of the penny has decreased (according to metals used)

Materials: 

• Pennies sorted by years: up to 1965, 1970, 1975,  etc.  5 years, 3 from each year per group.

• Triple Beam Balance with 0.1g bar, or electronic balance

• US Mint Fact Sheet (given out at end of lab)

Pre Lab Questions:

1. What do you think a penny is made of?

2. How much mass do you think a penny has?

Procedure:

1. Record the mass of a penny to the nearest 0.1g

2. Repeat for all 3 of the same year.  Record in Table 1

3. Calculate the average mass.  Record in Table 1.

4. Continue until all pennies are done.

Data::

Table 1: Penny Mass in grams

Table 2: Class data of average penny mass in grams

Analysis/Results:

1. What was the average mass of a penny for your years?
2. According to our class data, what year(s) had a difference in mass?  Support your answer with data.
3. What metal(s) are pennies made of?
4. How much mass does a dollar worth of pennies have?  Show your work!

OUT OF CURIOSITY:  

1. What is the going rate for the metal(s) used in a penny?
2. If the mass of a penny is different, does the density change? Hint: Density = Mass/Volume
3. Did you know that a dime has less  mass than a penny? That 2 pennies have as much mass as 1 nickel? Prove it!
4. More about the US MINT.

Conclusion: 2-3 sentences demonstrating what you learned in this lab.