Do you have acid rain? All you have to do to find out is to make this cabbage soup and add some rainwater!

Cabbage soup is a great acid-base (pH) indicator, and if you add something acid it will change color. It will turn pink for acids, and blue for alkaline (base). If it is not acid or base, it will stay the same. This means it is neutral.

The U.S. Environmental Protection Agency states that acid rain is a serious environmental problem. Scientists have confirmed that sulfur dioxide and nitrogen oxides—from electric power generators that rely on burning fossil fuels like coal—are the primary causes.

Learn here if the rain falling on your home is acid rain—the recipe couldn’t be simpler, and kids love the project.

MATERIALS
Red cabbage
Grater
A few clear glasses or containers
Sauce pan
Water
White vinegar
Baking soda

PROCEDURE
Make sure that you have adult supervision to use the stove!

Grate the cabbage until you have two cups. Place the cabbage in a sauce pan and put in enough water to cover the cabbage. Simmer for 15 minutes and let it cool. When it is cool strain the mixture and save the liquid.

Do your testing in a clear container or glass so that you can hold it up to the light to see the color changes more easily.

Use a little bit of your solution to test some different things. Add a tablespoon of vinegar to a tablespoon of your cabbage soup. What happens? It changes the color to blue.

This cabbage soup acid tester will change from pink for acids to blue for alkaline (base). If it is not acid or base, it will stay the same. This means it is neutral.

TESTING THE RAINWATER
Start collecting samples of rainwater in really clean jars (make sure that you rinse them really well).

Mix equal amounts of cabbage soup and rainwater and observe the variation in color.

To buy this wonderful book ($15), contact The Earth Child Institute.