Cabbage Soup Acid Rain Test

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.

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

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.

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.

Adapted from Every Body Counts, Every Drop Matters, by Donna L. Goodman (United Nations Publications, 2003).


Katie Spooner
Past Member 9 years ago

yes it will turn pink for vinegar, that's the way all these PH indicators work. By the way you can do this with many red substances. It even works for stuff like cranberry juice.

Jenn F.
Jenn F9 years ago

This is also a good way to make ph test strips. Jut cut up strips of newspaper (without print) and soak them in the liquid. then wait for them to dry and you are ready to start testing!

Jenn F.
Jenn F9 years ago

umm. sorry to point out the inconsistancies, but vinegar is an acid, and if the liquid turns blue for alkali, it will not turn blue for vinegar. Likewise if it does turn blue for vinegar, than blue liquid would indicate acid rain.