SciTec at Home: Elephant's Toothpaste Experiment

Introduction

• Presenter: Mita
• Experiment: Making Elephant's Toothpaste
• Misleading name: Not a dental hygiene program for large mammals
• Goal: Demonstrate the decomposition of hydrogen peroxide in the presence of dish soap

Chemical Reaction Overview

• Chemical Equation: H₂O₂ → H₂O + O₂
• Key Points:
  • H₂O₂ (hydrogen peroxide) breaks down into H₂O (water) and O₂ (oxygen)

Safety Precautions

• Hydrogen peroxide can be toxic at high concentrations
• Use protective equipment:
  • Safety glasses
  • Gloves

Experiment Materials

• Two solutions of hydrogen peroxide:
  • 6% concentration (weak)
  • 35% concentration (strong)
• Food coloring for visual effect:
  • Blue for weak solution
  • Red for strong solution
• Dish soap
• Potassium iodide (catalyst)
• Test tubes
• Graduated cylinders

Experiment Steps

1. Add dish soap to hydrogen peroxide solutions
   • Reason: Reaction forms oxygen gas which creates bubbles with soap and water
2. Add potassium iodide to solutions
   • Potassium iodide acts as a catalyst to speed up the reaction
   • Catalyst: Substance that increases reaction rate without being consumed

Predictions and Observations

• Weak solution: Slower bubble formation
• Strong solution (35%): Faster, more vigorous reaction

Home Experiment Variation

• Materials:
  • Old container of dishwashing liquid
  • 3% hydrogen peroxide (common from supermarket or chemist)
  • Yeast (as a catalyst)
  • Warm water
• Steps:
  • Wake up yeast with warm water
  • Add yeast to hydrogen peroxide and dish soap mixture
  • Use a funnel to reduce mess
  • Observe the reaction: Rapid bubble formation,