8 Demonstration: Disappearing Colors

Supplies:

Bleach

2 clear plastic cups

Food coloring

1 cup water

Dropper or plastic pippette

Question: What do you think will happen when we add bleach to colored water?

Directions: Add 1 cup water to a plastic cup and 2 drops food color. Gently mix by pouring the water into the second cup. Add a few drops bleach and transfer back and forth between cups to mix. The color should lighten or disappear.

Theory: Bleach works by oxidizing the color molecules, thus changing it from from reflecting color. This is similar to how bleach works to remove stains from clothing in the wash.Grades: 1st – 4th

Time: 5 – 10 minutes

Clean-Up: Contents can go down drain. Wash cups and reuse.

Notes and Hints: Give space between the experiment and the students. It may be best to wear glasses or safety goggles to avoid splashes. You may add more bleach if needed or more color to explore what happens.

Image Credit: https://www.messforless.net/easy-experiments-making-color-disappear/