| Here is a science project idea. Children in elementary | | | | squeeze a little out into the bottom of the cup and |
| school such as 4th through 6th grades would be able | | | | place the penny on the paste and then squeeze more |
| to do this as well as middles school 7th and 8th grade | | | | on top of the coin. |
| students. In this science project you will determine | | | | For the baking soda mix a slight amount of water with |
| which substance has the most acid in it to clean tarnish | | | | the soda to form a paste and do the same as with |
| off of coins. | | | | the toothpaste making sure the bottom and top of the |
| Items you will need for the project: | | | | penny is covered with the substance. |
| - 8 cups | | | | Let these glasses of liquid sit overnight at room |
| - 8 tarnished copper pennies | | | | temperature. |
| - Tomato juice | | | | In the morning place a paper towel in front of each |
| - Lemon juice | | | | cup. Remove each penny from the liquid it has been |
| - Vinegar | | | | sitting in and gently rub and wipe the outside of the |
| - Window cleaner | | | | penny. Use a different paper towel for each coin. |
| - A household cleaner like simple green or fantastic | | | | After you are finished with all eight make a visual |
| - Ammonia | | | | observation. What does each penny look like? Also |
| - Toothpaste | | | | look at the paper towel to determine which one has |
| - Baking soda | | | | the most tarnish on the paper. Using your graph paper |
| - Paper towels | | | | record each substance and make a bar graph |
| - Graph paper | | | | showing how much tarnish each one removed. |
| For this experiment you will determine from the | | | | When you started you should have made a |
| constant, the tarnished copper penny, which of the | | | | hypothesis about which substance would remove |
| liquids or materials removes tarnish the best. | | | | tarnish the best and why it would remove the tarnish |
| Line up your glasses in a row on a counter top. Make | | | | effectively. Was your theory correct? |
| sure you will not be using this space for something | | | | This science project is great for middle school or high |
| else. The best time to do this is in the evening so that | | | | school. It can even be done by a younger student in |
| you can let the pennies soak overnight. | | | | 3rd or 4th grade. Make sure to have your parent help |
| Fill each cup with one of the ingredients. You should | | | | with the chemicals by pouring them into the glasses |
| now have 8 cups with a different substance in each. | | | | and disposing of them. You may want to wear gloves |
| You do not need more than about 1/8 cup of each | | | | with the various chemicals. |
| ingredient. Just use enough for the penny to be | | | | Science project ideas can be found in your own home |
| submerged under the liquid. For the toothpaste | | | | cabinet. |