First order kinetics
What First order kinetics means in Chemistry A-Level, as defined for OCR.
Definitions of First order kinetics
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Reference: OCR
A reaction in which the half-life is constant and independent of concentration, so the time for the reactant concentration to fall from any value to half that value stays the same as the reaction proceeds.
A reaction whose rate is proportional to the concentration of one reactant, so its concentration–time curve falls steeply at first and then flattens.
Topics that use First order kinetics
- 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 First order kinetics in the exam
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