Main Subject Area: Science
Duration of Lesson: 45 minutes
Additional Subject Area Standard(s):
Students will create their own battery.
A mild soap to clean your coins
Salt water solution
4 paper napkins
Voltmeter (available at hardware stores, need just one for whole class)
Coins Used in Lesson:
Grade Level(s): 3-5 6-8
1. To create the battery, students should first clean their coins with the soap.
Note- Remember, do not perform this experiment with any coins that you may be saving for a collection. Washing coins is not recommended for coins intended for a coin collection.
2. Next, soak the napkins in the saltwater solution.
3. Now have your students create a “sandwich” with the coins and the napkins. Fold the napkins until they are just a little big bigger than the coins. Alternating a penny, napkin, and then a dime, create a sandwich or stack. Make sure the ends of the stacks are different coins. Connect a voltmeter to the ends of the stack.
Why does this work? The saltwater solution is an electrolyte. It reacts with the metals, which are electrodes. Since there are two kinds of metals (in the two different coins) one metal reacts more strongly than the other, which leaves an electrical potential difference (voltage) between the two types of metals.
Assessment / Evaluation:
Differentiated Learning Options: