- To demonstrate how dyes work in acidic environments by attaching to other molecules through bonding.
- To describe why dye is so pleasing to the eye.
The other day I tried to think of a creative way to make ladybug eggs for a STEM activity for children. Ladybug eggs are typically yellow and oblong in shape. How perfect, I thought, to use rice. I dyed the white rice in my pantry yellow using food coloring, and did not need to make a trip to the grocery store just to buy yellow rice. Took about…oh…10 minutes from start to finish.
Whether you dye rice or eggs, the process works because the color molecules attach to the surface of your item by forming bonds. In adding an acid such as vinegar to the mix, you create a more optimal environmental “soup” of positively-charged hydrogen ions enabling the negatively-charged dye to bind to the surface even better.
These colors look magnificent to us because of the science of light absorption and reflection. Dye molecules absorb white light and reflect light of various wavelengths. We see the reflected visible light as colors that are pleasing to our eyes.
All you need is a plastic bowl, white rice, vinegar, food coloring, a plastic spoon, and some paper towels or a paper plate. Add approximately 1 tsp of vinegar to about 1 cup of rice and mix. Add a few drops of food coloring and continue mixing until the dye completely covers the rice. Allow the rice to dry by spreading it out on a paper towel or paper plate for several minutes.
Now that you are a dye guru, don’t stop there. Try to use different colors. Put the rice in closed plastic containers to make shakers. Glue the rice on paper to make creative patterns. This activity can also be used in sensory play. Further, placing some colored rice in a nice glass jar with a bow also makes a unique decorative homemade gift.
So very colorful…so very pleasing to the eyes.