In the laboratory, chemists use ready-made test sticks (pH indicators) that can change color to determine whether a liquid is acidic. Unfortunately, we don’t have anything like that at home. But we can make our own “test tool”: with radish juice. How does radish juice change color when it comes into contact with liquids with different acidities?
Radish juice is red, right?
You will need
- Approximately 140 g radishes
- Glass bowl
- Measuring cup
- Cutting board and knife
- Empty jam jars
- Tap water
- “Test liquids”: dishwashing liquid, citric acid solution, aqueous solution of baking soda
Let’s get started!
1. Weigh radishes and cut into small pieces
Weigh 140 g of radishes and carefully chop them with a kitchen knife.
2. Infuse in water
Pour as much hot water from the faucet as possible over the radishes and let everything steep for about 15 minutes.
Pour the radish juice through a sieve into a glass jar (e.g., empty jam jar).
4. Prepare tests
Now you can choose the liquids you want to examine with the radish juice. You need a separate jar for each liquid that you want to examine. Place a piece of paper in front of each jar and number the pieces of paper from 1 to 5.
For example, you can test:
50 ml tap water + 50 ml citric acid.
90 ml tap water + 10 ml dishwashing liquid
100 ml distilled water
100 ml tap water
100 ml tap water + 1 teaspoon baking soda
5. Use juice as pH indicator
Now add 2 tablespoons of radish juice to each glass. What colors does the juice take on?