Science Experiment: Chemical Reaction – Penny Cleaner

Science Experiment: Chemical Reaction – Penny Cleaner

Chemical ReactionsEverything in the universe is made of teeny tiny particles called atoms.srppennysetup Some things are made up of just one kind of atom. A penny is made up entirely of copper atoms. Atoms can join together to make molecules. When a penny is exposed to oxygen in the air, the copper atoms of the penny and the oxygen atoms in the air combine. A chemical reaction takes place that makes a molecule called copper oxide – that is the dirty stuff that you see on the penny.  This “stuff” is often referred to as “tarnish.” When you soak the pennies in taco sauce, another chemical reaction takes place. Try this experiment to watch this chemical reaction.




You Will Need:

  • Dirty Pennies
  • Taco Sauce
  • Vinegar
  • Tomato Paste
  • Salt
  • Water
  • Small Plates
  • Masking Tape

Put some tarnished pennies in a small dish and pour taco sauce over them. Let the taco sauce sit for a few minutes and then wash the taco sauce off the pennies. How do the pennies look now? If you look at the ingredients in the taco sauce you will notice that the main ingredients are tomato paste, vinegar and salt. Which ingredient affected the tarnish on the pennies? To find out, you need to test different combinations of the ingredients. First, try to polish the pennies with just tomato paste, just salt and just vinegar. How do the pennies look? Then, try polishing the pennies in different combinations of the ingredients: tomato paste + salt, vinegar + salt and tomato paste + vinegar.  Which combination worked best? To investigate chemical reactions further – try some more experiments at home.

Websites, Activities, Printables & Databases:

Science in Context: Chemical Reactions is a database you can use in any IndyPL Library Branch or at home. Login using your IndyPL library card number. The Science in Context database will show you articles, images and videos to help you learn about chemical reactions.​


You can also ask a math and science expert for homework help by calling the Ask Rose Homework Hotline. They provide FREE math and science homework help to Indiana students in grades 6-12.


Use your indyPL Library Card to check out books at any of our locations, or check out e-books and e-audiobooks from home right to your device. Click on a book jacket below to request a book or download it. Need help? Call or ask a Library staff member at any of our locations, text a librarian at 317 333-6877, or leave a comment.

Crazy ConcoctionsExploring Kitchen ScienceKitchen Science Lab for KidsScience Experiments that Fizz and Bubble

Print This Post Print This Post

10 Responses »

  1. I think it would matter how big the sponge was and what it was made of. Is it a natural sponge or a synthetic one?

  2. sup peeps i am awesome u r all awesome save all hurt animals.
    thanks 4 the expirement im using this to help me with my project thx thx thx 😀


Leave a Reply

Your email address will not be published.

11 − 9 =