Chemistry A-Level
Pre-equilibrium and intermediates
What Pre-equilibrium and intermediates means in Chemistry A-Level, as defined for OCR.
Definition of Pre-equilibrium and intermediates
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Reference: OCR
A fast equilibrium that produces an intermediate before the slow step, so the intermediate's concentration may need to be substituted using the equilibrium expression.
Topics that use Pre-equilibrium and intermediates
- How fast? (OCR A-Level)
Related terms
- Calculating rate and concentration from the rate equation
- Colorimetry
- Concentration–time graphs
- Constant half-life
- continuous monitoring
- Controlled comparison of experiments
- Deducing order from initial-rate data
- Deducing order with respect to a reactant
Using Pre-equilibrium and intermediates in the exam
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