Question

Vinegar is an acid. Which liquids produced colors like vinegar?

Ammonia is a base. Which liquids produced colors like baking soda or ammonia?

Did you see any that did not fit into either color group? If so which one(s)?

How would you be able to tell when a neutral pH was obtained?

What did you find out from this investigation? Be thoughtful in your answer.
Why did some substances require larger additions before a color change was seen?

What does this indicate about the strength of the acid or base?
What happened in the final step of the experiment?
What does the final color

Answer 1

Form a hypothesis concerning the household products to be tested in this experiment. Which ones do you believe will be acidic? Which will be basic?
2. Divide one piece of notebook paper into three sections. Label the first vinegar (acid), the second baking soda or ammonia (base), and the last distilled water (control). Place a small cup for testing on each section.
3. Fill the three small cups about half full with cabbage juice.
a. Add a small sample of vinegar to the first cup and record results. (About 2.5 mL [1/2 teaspoon] vinegar is required for a 50-mL sample of cabbage juice.)
b. Add a small sample of baking soda or ammonia to the second cup and record results.
c. As a control, add a small amount of distilled water to the third cup and record the results.
4. Divide the second piece of notebook paper into 6 equal sections. Label each with the name of a household liquid to be tested.
5. Fill 6 small cups about half full with cabbage juice and place them on the labeled notebook paper.
a. Test each with the appropriate solution and record the results.
b. Hint: If no color change is seen, try making a second addition. If no change is seen, try one more time. Use the control for comparison.
6. Pour the solution from 3b above into a slightly larger, clear container. Slowly add the solution from 3a above. Record your results.