University of Virginia
Physics Department

Decomposition of Hydrogen Peroxide

A Physical Science Activity

Student Activity

Materials

Procedure

  1. Pour about test tube full of hydrogen peroxide. Analyze the liquid.
  2. Add about a pinch of yeast to the hydrogen peroxide. Shake it until well mixed and put the cork on the test tube.
  3. Test the bubbles of gas foaming out of the solution with first a flaming, then with a glowing wooden splint. Keep relighting the splint until the reaction stops.
  4. Analyze the product left in the test tube at the end. What do you think it is?
  5. Clean up the test tube and be sure wooden splints are extinguished before disposing of them.

 

Assessment

  1. Describe the odor, color, viscosity, and flammability of hydrogen peroxide.







  2. What happened when you put the cork on the test tube? Using what you know about the particle theory for matter, explain why this happened.







  3. What kind of gas was produced by this reaction? What evidence do you have to prove this?








  4. What do you think was left in the test tube at the end? Describe some of its properties. Is it the same substance that you started with?







  5. What role does the yeast play in this chemical reaction?







  6. Write a chemical equation for this reaction, using coefficients to balance the equation if necessary.







  7. What evidence do you have that this was a chemical change and not a physical change?