Grades 1–2
Capillary action is the name for the process that takes place when a paper towel soaks up a spilled liquid or when a plant transfers water from its roots to its leaves.
What You Need
- 4 same-size stalks of fresh celery with leaves
- 4 cups of the same size
- Knife < !!! >
- Vegetable peeler < !!! >
- Red and blue food coloring
- Measuring cup
- Paper towels
- Ruler
- Old newspapers
- Water
What to Do
Lay the four stalks of celery in a row on a cutting board or counter so that the place where the stalks and the leaves meet matches. Cut all four stalks of celery 4 inches (about 10 centimeters) below where the stalks and leaves meet.
Use 10 drops of red and 10 drops of blue food coloring for each 1/2 cup of water to make purple water. Pour the colored water in equal parts into the four cups. Have your child put one stalk each in the cups of purple water.
Label four sheets of paper towels: "2 hours," "4 hours," "6 hours," and "8 hours." (You may want to put newspapers under the towels.) Every two hours, have him remove one of the stalks and put it on the correct towel.
Each time he removes a stalk from the water, help him to carefully peel the rounded part with a vegetable peeler to see how far up the stalk the purple water has traveled.
Help your child to measure the distance the purple water has traveled for each stalk and record the information in his science journal. Talk with him about what he has observed.
Work with your child to make a list of other objects around the house or in nature that illustrate capillary action. Have him look for paper towels, sponges, old sweat socks, brown paper bags and flowers.
