The Traveling Colors
Updated: Aug 28
What is the traveling colors experiment? With this science activity, you will explore the wonderful world of capillary action through water and colors.
Water is an essential part of our lives. We need water to survive, it helps regulate our body temperature and carries nutrients throughout our bodies, and provides nourishment. Water has the ability to flow without the help of external forces.
Water gets pulled into these fibrous gaps by capillary action. This is the same phenomenon that allows trees to suck water out of the ground. This action is partially fueled by surface tension, which is caused by water molecules being attracted to one another. Surface tension is what allows water to form beads instead of spreading out, and for some small insects to walk on water. It also allows water to get sucked into narrow tubes or gaps in materials.
This simple science experiment will help you create your very own rainbow by allowing colors to travel. Have fun, STEM Warriors!
WHAT YOU NEEED
1. 7 Plastic Cups
2. Pitcher or Bottle of Water
3. Red, Blue, or Yellow Food Coloring
5. Paper Towels
6. Measuring Cup
WHAT YOU DO
1. Get a piece of paper towel and ensure it is facing you horizontally. Fold it in half twice. Then, fold it in half lengthwise or vertically.
2. Cut around half an inch at the end of the folded paper towel. Create 5 more folded paper towels.
3. Arrange your plastic cups in a straight line.
4. Measure 1/2 cup of water. Pour it into the first cup. Do the same thing to the other cups in an alternate manner. So cup 1 with water, cup 2 with no water, cup 3 with water, and so on.
5. Add 2-3 drops of food coloring to those cups with water - red, blue, yellow, and red.
6. Unfold the paper towels. Connect them together by placing one end of the paper towel in one cup while the other end in another cup.
7. Observe how the colors travel for 5-10 minutes.
The water moves up the paper towels along with the food dye molecules due to capillary action. The fibers that are found in plants are the same as those found in paper towels and are called cellulose. The water molecules stick to the cellulose fibers in the paper towel because of adhesion. These molecules are also attracted to each other and try to stick close together, this process is called cohesion. This cohesive force helps absorb water and the water travels through the gaps in the paper towel and into the empty glass. The attractive forces between the water and fibers in the paper towel help the water move upwards against gravity.
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