What Is Electroplating?
Before beginning this chemistry experiment, prepare your students by teaching them what electroplating is. Let them know that electroplating is the process of placing one metal over another and is usually done to protect the metal it is covering. If possible, bring in a piece of jewelry that has electroplating that has worn off. Show students what happened to the original metal under the electroplating. The metal may be a greenish color or leave green on their hands when they touch it.
You are going to be doing a simplified form of electroplating in your classroom using simple materials that can be found in any home. Read the section below to perform this experiment.
For this electroplating copper experiment you will use the materials listed below:
- 2 cups of vinegar
- glass jar, such as a pickle or jelly jar
- 6 dirty pennies
- 1 teaspoon of salt
- 3 clean nails or paper clips
Creating the Electroplating Solution
Fill the jar with vinegar. Mix the teaspoon of salt in with the vinegar. Place dirty pennies in the vinegar and allow the solution to clean them. Once the pennies are clean, remove them from the solution. Move on to the next step of the chemistry experiment.
For the next step of the experiment you need the clean nails or metal paper clips. For use in this process they should not have a coating or electroplating of any kind. Follow the instructions below to complete the copper electroplating experiment.
- Once you have removed the pennies from the solution and rinsed them off, show them to the students so that they can see that the pennies are now clean. Explain to the students that the "dirt" that was removed was actually copper oxide. When this dissolves in the solution, it forms copper, even though they can't see it. This copper has a natural attraction to other metals.
- Place 2 of the nails or paper clips in the solution.
- Let the nails sit in the solution for a couple of hours. It may even work best if you prepare the solution and place the nails in it at the end of the day and allow it to sit overnight so that the students will get the full effect of the project on the next school day.
- Take the nails or paper clips out of the solution.
- Compare the nails or paper clips from the solution to the ones that were never put in the solution. The ones from the solution should now be a different color because they are covered with a copper coating. Allow students to discuss the differences in the colors.
Explain to the students that the copper atoms were searching for a metal to attach to because the removal of the atoms left the atoms with a negative charge. Once the nails are placed in the solution, some of their atoms a removed as well. This removal process leaves them with a negative charge that the copper atoms are attracted to. This is the reason the copper atoms are now stuck to the nails.
Try using other materials to see how well the copper atoms stick to them. If you need to create more copper in the solution, simply add more dirty pennies!