Chemistry A-Level
iodine clock
What iodine clock means in Chemistry A-Level, as defined for AQA.
Definition of iodine clock
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Reference: AQA
A method where a limited amount of thiosulfate consumes the iodine until it runs out and the starch suddenly turns blue black, so the same tiny extent of reaction occurs each time.
Topics that use iodine clock
- Determination of rate equation (A-level only) (AQA A-Level)
Related terms
- Constant half-life
- continuous monitoring
- deriving the rate equation
- evidence for mechanism
- multi step mechanisms
- orders and molecularity
- rate against concentration graphs
- Rate-determining step
Using iodine clock in the exam
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