Racing Color Changes

Racing Color Changes is a visually stimulating science project for kids.
Acid fighter to the rescue! Find out which antacid tablet is the best.

Fun Fact
Antacids work by absorbing the hydrogen ions that are released by acids. The antacids combine with the acid and produce salt and water. Most antacids contain calcium, magnesium, or aluminum.

What You'll Need:

  • Goggles
  • Rubber gloves
  • Measuring cups
  • 1/4 head of cabbage
  • 3 test tubes
  • Ammonia
  • Strainer pot
  • Sauce pan
  • Knife
  • Water
  • 4 glasses
  • Pipette (or eyedropper)
  • Vinegar
  • 2 different brands of antacid tablets
  • Large wooden spoon
  • Glass bottle with lid
  • 2 science stirrers (or coffee stirrers)

Racing Weird Color Changes is an eye-popping science project for kids.
©2007 Publications International, Ltd.
Racing Color Changes is an eye-popping science project for kids.

How to Learn About Racing Color Changes

Step 1: Cut cabbage into chunks. Put cabbage into the saucepan with 2 cups water. Heat to a low boil on the stove. Turn off the heat, and let water cool.

Step 2: Pour the cabbage juice through the strainer into a pot. Use a funnel to pour the cabbage juice into the bottle. Throw away the cabbage. You have made cabbage juice indicator.

Step 3: Test your cabbage juice indicator. Put on the goggles and rubber gloves. Put 2 tablespoons indicator into each test tube. Add 2 tablespoons water to each test tube to dilute the indicator.

Safety
This activity should be done with adult supervision. Never use medicine without adult approval. Wear goggles and rubber gloves when using ammonia and vinegar. Avoid skin contact with ammonia. If ammonia gets on your skin, wash immediately with lots of water. Wear goggles when working with cabbage juice indicator and vinegar.


Step 4: Add a few drops of vinegar to the first test tube, a few drops of ammonia to the second test tube, and a few drops of water to the third test tube. (Rinse pipette well between liquids.) Compare the color in each test tube.

Step 5: Dilute the cabbage indicator by adding 1/4 cup cabbage juice to 2 cups water in a glass. Add a few drops of vinegar until the cabbage indicator has a reddish color.

Step 6: Pour 1/4 cup diluted cabbage indicator into each of 3 glasses.

Step 7: Gather the different antacid tablets. Crush 2 tablets of each antacid with the back of the wooden spoon. Be sure to keep the brands separate.

Step 8: Place the crushed tablets of the first antacid into the first glass. Place crushed tablets of the second antacid into the second glass. Don't put anything into the third glass -- this is the control.

Step 9: Stir each glass the same amount every 5 minutes. After 40 minutes, compare the colors in the glasses. Which antacid caused the biggest change in color?

What Happened?
The vinegar causes the cabbage color to change to red. As the antacid tablets dissolve, they neutralize some of the acid. This causes slow color changes in the cabbage indicator. The solution with the biggest color change is the stronger antacid.


Erupting Weird Color Flow is a dramatic science experiment for kids that creates the spectrum of colors with chemicals. Read about it on the next page of science projects for kids: spectrum of colors.

Looking for more science projects to do with your kids? Try: