Science Fun

Fizzy Fruit and pH Indicator

Materials:

  • 3 containers
  • Pipettes (you can also use squirt bottles or straws to transfer)
  • Baking Soda
  • Clementine or any kind of acidic fruit
  • Small Cups
  • 1/4 teaspoon
  • 1/2 cup

Instructions:

  1. Dilute a small amount (less than ⅛ tsp) of Red Cabbage Jiffy Juice Powder in approximately 4 cups of water to create your pH indicator. You are just looking for the liquid to be a purple color. Fun Fact: You can make your own ph Indicator by boiling red cabbage and extracting the pigment or even cranberry juice.
  2. Pour equal amounts of the pH Indicator in the 3 different containers
  3. One jar will be labeled as your control. Since it will only contain water, it should ideally have a pH of 7 (neutral).
  4. Mix approximately ¼ tsp of baking soda with ½ cup water in a small cup.
  5. Use your pipette or straw to transfer your baking soda mixture into one of the pH indicator jars. Notice and observe any color changes.
  6. Use your clementine or acidic fruit and mash it up to extract some juice. Pour the juice into the last indicator jar and notice a color change.
  7. Compare the jars and have a discussion about the difference between acids and bases and the pH scale.
  8. As a fun way to conclude, use some of the fresh acidic fruit juice and mix it with some baking soda and notice a reaction occur. You should notice bubbles. After you observe, you can have the students dip a piece of their clementine in a small amount of baking soda and eat it. They will be able to notice the bubbles forming in their mouth. (This is one of the coolest parts of this whole experiment).

How It Works:

In the presence of water, citric acid [C6H8O7] and sodium bicarbonate [NaHCO3] (aka baking soda) react to form sodium citrate [Na3C6H5O7], water, and carbon dioxide [CO2].