Chemical Kinetics

 

Alka Seltzer in Water at Three Temperatures –Three students add Alka-seltzer tablets to flasks containing water at different temperatures and quickly seal the flasks with stoppers fitted with balloons, which will inflate at different rates.

Briggs-Rauscher – Introduce the mystery of mechanisms with the Briggs-Rauscher Oscillating Reaction.

Catalysis of a Reaction – Demonstrate the catalysis of the H2O2 decomposition of NaK-tartrate with Co2+. Adding Co2+ turns the solution pink, but the solution quickly turns dark green as it begins to react vigorously. At the end of the reaction, the pink color is restored, showing regeneration of the catalyst.

Elephant Toothpaste – Demonstrate the decomposition of 30% H2O2 in the presence of dishwashing liquid and KI, producing an upsurge of steaming foam.

Genie in a Bottle – Use MnO2 to catalyze the decomposition of 30% H2O2, producing a large cloud of hot water vapor. The heat generated is intense enough to shrink the 2 L bottle used for the demo.

Iodine Clock – Perform the iodine clock reaction with three different initial concentrations of IO3.

Light Sticks – Immerse light sticks in hot and cold water to show variation in rates depending on temperature

Lycopodium Powder Combustion – Contrast the rate of combustion of a pile of lycopodium powder versus the exploding paint can.

Reaction Intermediates – Add FeCl3 (aq) to Na2S2O3 (aq) on the overhead projector, giving rise to the black intermediate FeS2O3+, which forms and disappears, leaving colloidal sulfur as the final product.

Steel Wool Reaction Rates – Contrast the burning of steel wool in air and in a flask charged with O2 (g)

Surface Area Reaction Rate: Iron Strip and Powder – Contrast the results of holding a strip of iron in a burner versus squirting powdered iron into the burner flame