Magic Genie

Alternate titles:

Genie Bottle

Purpose:

To demonstrate the rapid effect a catalyst has on the thermal decomposition of hydrogen peroxide.

Materials:

• 100mL beaker
• Rubber stopper
• 500mL Florence flask covered with duct tape

Reagents:

• Manganese dioxide (MnO_2(s))
• 30% Hydrogen peroxide (H₂O₂)

Hazards and PPE:

• Hydrogen peroxide at high concentrations is highly combustible. Store and handle with care.
• Manganese dioxide is an acute toxin. Handle with care.
• This reaction is extremely exothermic. A safety shield is recommended.
• Wear approved safety goggles and gloves.

Protocol:

Preparation

1. Place about 2 spatulas of manganese dioxide into a Kimwipe, form it into a loose pouch, and tie it closed with a 20 cm piece of string.
2. 10-30 minutes before the demo, measure out ~50mL 30% H₂O₂ and pour it into the Florence flask. This will give the hydrogen peroxide some time to come to room temperature.
3. Carefully suspend the pouch above the hydrogen peroxide and hold it in place by the string with a rubber stopper.

Demonstration

1. If you like, tell up a story about a magic bottle.
2. Remove the stopper and step back. A large puff of steam will be released.

Additional Notes:

• Forming the MnO₂ pouch too tightly/too small will limit the catalysis.
• 10% hydrogen peroxide can be used, but the reaction will not be as dramatic.

Disposal:

• The liquid and the pouch containing MnO2 should be poured into an appropriately labeled bottle.
• Be sure to thoroughly clean flask to ensure that the demo will work the next time it is used.

Reactions:

• 4H₂O_2(aq) → 2H₂O_(l) + O_2(g)
• The manganese dioxide serves as a catalyst.

Citations:

1. ICE Demonstration Workshop, University of Arizona, 1986.

Videos:

• Magic Genie

  FlinnScientific