Oscillating Clock
- Page ID
- 3126
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The Briggs-Rauscher reaction is an oscillating reaction like the Belousov-Zhabotinsk reaction.
Introduction
Reactions
The essential features of the system depend on two key processes, each involving many reactions working together:
- A ("non-radical process"): The slow consumption of free iodine by the malonic acid substrate in the presence of iodate. This process involves the intermediate production of iodide ion.
- B ("radical process"): A fast process involving manganese and free radical intermediates, which converts hydrogen peroxide and iodate to free iodine and oxygen. This process also can consume iodide up to a limiting rate.
IO3- + 2 H2O2 + CH2(CO2H)2 + H+ -> ICH(CO2H)2 + 2 O2 + 3 H2O
The striking visual demonstration occurs by the addition of a starch indicator.
Safety
Do not drink this.