By Kathryn Hatter
Updated Aug 30, 2022

Explore the science behind turning colored water clear with everyday household items. This experiment demonstrates how chlorine bleach and baking soda work together to oxidize and neutralize food coloring, providing a visual lesson in chemical reactions while emphasizing safety.

Safety First

• Use a well‑ventilated area and wear gloves if desired.
• Avoid inhaling bleach fumes; keep the experiment out of reach of children.
• Never ingest any of the chemicals used.
• For detailed safety guidelines, see OSHA Chemical Safety.

Materials

• Clear glass or cup
• Cool tap water
• Food coloring (approximately 3 drops)
• Household chlorine bleach (2 tbsp.)
• Baking soda (½ tsp.)
• Spoon or stir stick
• Measuring spoons

Procedure

Step 1 – Prepare the Colored Solution

Place three drops of food coloring into the bottom of the glass. Fill the glass halfway with cool water and stir until the color is evenly dispersed.

Step 2 – Add Bleach

Pour approximately 2 tablespoons of chlorine bleach into the colored water. Stir gently; you will notice the color lightening, but it will not vanish entirely.

Step 3 – Introduce Baking Soda

Sprinkle about ½ teaspoon of baking soda into the mixture and stir again. Within seconds, the solution will turn clear as the baking soda accelerates the oxidation process.

Scientific Insight

Bleach releases hypochlorite ions, which oxidize the dye molecules. Baking soda raises the pH, speeding up the reaction and helping to neutralize the colorants. The result is a transparent solution, illustrating how oxidation can reverse visible staining.

Conclusion

This simple demonstration not only showcases a neat visual effect but also reinforces key concepts in chemistry: oxidation, pH influence, and safe handling of household chemicals.