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Cabbage Magic
 Chemists and cooks need to know the difference between acids and bases. In cooking, acids give flavour to food. Bases help foods, such as cakes, rise. How do you tell the difference? With cabbage juice of course!
What You Need
Grater
½ red cabbage
Large bowl
Water
Strainer or slotted spoon
Small spoon
4 small paper cups or glasses
Cream of tartar (potassium bitartrate)
Baking soda (sodium bicarbonate)
Vinegar (acetic acid)
Lemon juice (citric acid)
What to Do
1. Have an adult help you grate the cabbage into the bowl.
2. Cover the cabbage with water and set aside for at least 2 hours.
3. Use the slotted spoon or strainer to remove the cabbage.
4. Half-fill each cup with cabbage juice.
5. Add one spoonful of baking soda to the first cup. Stir. What happens?
6. Clean the spoon and then add cream of tartar to the second cup.
7. Repeat, adding vinegar to the third cup, and lemon juice to the fourth.
8. Repeat the experiment using other ingredients you can find in your kitchen, such as tea, juice, pop, milk, or soap.
How it Works
Acids and bases are important in chemistry, but also in cooking. Scientists use indicators to tell if something is an acid or a base. The cabbage juice is an indicator. It changes colour when acids or bases are added to it. Acids turn the cabbage juice pink. Bases turn the cabbage juice blue or green. Do you put an acid or a base on your french fries?
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