Items you will need for the project:



8 cups

8 tarnished copper pennies

tomato juice

lemon juice

vinegar

window cleaner

a household cleaner like simple green or fantastic

ammonia

toothpaste

baking soda

paper towels

graph paper

For this experiment you will determine from the constant, which is your tarnished copper penny, which of the liquids or materials removes tarnish the best.

Line up your glasses in a row on a counter top. Make sure you will not be using this space for something else. The best time to do this is in the evening so that you can let the pennies soak overnight.

Fill each cup with one of the ingredients. You should now have 8 cups with a different substance in each. You do not need more than about 1/8 cup of each ingredient. Just use enough for the penny to be submerged under the liquid. For the toothpaste squeeze a little out into the bottom of the cup and place the penny on the paste and then squeeze more on top of the coin.

For the baking soda mix a slight amount of water with the soda to form a paste and do the same as with the toothpaste making sure the bottom and top of the penny is covered with the substance.

Let these glasses of liquid sit overnight at room temperature.

In the morning get a paper towel and place in front of each cup. Remove each penny and gently rub and wipe the outside of the penny. Use a different paper towel for each coin.

After you are finished with all eight make a visual observation. What does each penny look like? Also look at the paper towel to determine which one has the most tarnish on the paper. Using your graph paper record each substance and make a bar graph showing how much tarnish each one removed.

When you started you should have made a hypothesis about which substance would remove tarnish the best and why it would remove the tarnish effectively. Was your theory correct?

This science project is great for middle school or high school. It can even be done by a younger student in 3rd or 4th grade. Make sure to have your parent help with the chemicals by pouring them into the glasses and disposing of them. You may want to wear gloves with the various chemicals.

Science project ideas can be found in your own home cabinet.