Oscillating Colour Change

We use three chemical solutions to create an oscillating reaction. The three different solutions are mixed using a magnetic stirrer and the colour changes from clear to amber to dark blue. This pattern repeats as the concentrations of iodine, iodide ions and starch change within the beaker. Eventually the reaction stops, leaving the solution dark blue.

Chemistry - Reactions - Learning Points.
Some chemical reactions go in one direction and then reverse themselves - this is known as an oscillating reaction.
Not all reactions start with reactants and end with products.
A chemical equilibrium is the state in which the concentrations of reactants and products do not change anymore.

A Twig Experiment Film.
Let students experience real experiments in lab conditions anywhere, from setup, method all the way through to analysis and real-world application.