Investigate the Kinetics of the Color Changing Iodine Clock Reaction

[LaylaHall]

Can you explain what Iodines are and their role in the experiment?


[Administrator note: Project: https://www.sciencebuddies.org/science- ... n-kinetics ]

[DauntlessDog12]

Hi LaylaHall,

Iodine is the main ingredient in this chemical reaction because of how it operates with the 2 main reactions over time. The first chemical equation explains that the Iodine ions are giving away two electrons to the Hydrogen atoms so that they can join the H2O2 molecule and form two H2O's. This lets the Iodine ions form into Triiodide. The second equation for Iodine is where the inverse reaction happens, where Triiodide converts back into three Iodine ions from a reaction with Vitamin C. Before splitting into three Iodine ions, however, the triiodide reacts with the starch to create a blue color. Iodine is very important for this chemical clock because it accounts for the blue hue.