Dirty Pennies Experiment
- dirty/tarnished pennies
- 3 dishes/bowls
1. Fill one bowl with water.
2. Fill one bowl with soapy water.
3. Fill one bowl with about 1/2 cup of vinegar and 2 tsp. of salt and mix.
4. Discuss the different solutions and form a hypothesis as to what you think will happen to the pennies in each solution.
5. Place the pennies in the bowls and leave for 5 min. or more.
6. While leaving the original pennies alone, take a different penny and dip it halfway into the vinegar solution for about a minute. Then look at the penny together. (You should be able to see a difference in regards to the cleanliness of the dipped side.
Pennies get dull and dirty because the copper in the pennies reacts with oxygen in the air to form copper oxide. When you put your pennies in a vinegar and salt mix, the vinegar and salt react together and remove the copper oxide.
There is an extension activity that goes along with the statue of liberty that you could continue following this activity or save for later. I'm going to save it for later in the week when we focus on the statue of liberty and other American symbols. For the extension activity you leave the pennies that were in the vinegar solution out of the solution without washing them for about an hour. They will turn green like lady liberty.
If you don't wash the salt and vinegar mix off, a blue-green layer forms on the pennies. The salt and vinegar mix speeds up the reaction between copper and oxygen in the air, forming copper oxide - which is a blue-green colour. It's the same reaction that makes the Statue of Liberty green!
On a completely separate note, I've discovered that my picky eater, Lillian, will eat just about anything if it is a "Mommy Special". She loved the snacks/meals I've made that are themed for each week and now she requests them. Tonight I was not prepared for a special and had to do some quick thinking. I found these spiral hot dogs on a stick/"fireworks" and thought that I could probably manage that. However, Arthur had other plans and I had to work more quickly than expected. Plus, I couldn't find my star cookie cutter. So I just gave the items of the meal a fun name. They enjoyed: twisty dogs, All-American Mac n' Cheese, "Money" Honeydew and Freedom Carrots. Lilly had two twisty dogs and ate everything but the macaroni = success. The best thing about the "Mommy Special" is I can make ANYTHING I want and she doesn't complain! It's genius! Muah-ha-ha-ha-ha!!!