Chemistry Pop Guns

DESCRIPTION:
This demo harnesses the reaction of baking soda and vinegar to blow a cork off a test tube.
NaHCO3 (s) + CH3COOH (aq) →CO2 (g) + H2O (l) + CH3COONa (aq)

TOPICS COVERED:
acids and bases
pressure
organic reactions
evolution of a gas
chemical change

MATERIALS NEEDED:
– vinegar
– baking soda
– test tube
– cork

PROCEDURE:
1. Squirt a pipet full of vinegar into a test tube
2. With the test tube held sideways, carefully place some baking soda on the inside wall of the test tube and cork
3. Tilt the test tube back (allowing the baking soda to fall into the vinegar) and lightly shake
4. Aim the test tube towards a wall

ADDITIONAL COMMENTS:
There is an art of aiming the test tube before the reaction starts. The cork should be firmly in the test tube. This is a messy demo that can be done as an activity if you are willing to clean after.

SAFETY:
The test tube should never be aimed at another person, and anyone in the room with this should wear safety glasses. Caution should be taken when shaking the test tube.

REFERENCES:
Shakhashiri, B.Z. Chemical Demonstrations;  University of Wisconsin Press: Madison, 1989; Vol. 3, pp 96 – 98.

Handout