Chemistry A-Level
tangents and initial rate
What tangents and initial rate means in Chemistry A-Level, as defined for AQA.
Definition of tangents and initial rate
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Reference: AQA
On a concentration against time graph, the rate at any moment is the gradient of the tangent, and the initial rate is the gradient at time zero.
Topics that use tangents and initial rate
- Determination of rate equation (A-level only) (AQA A-Level)
Related terms
- Constant half-life
- continuous monitoring
- deriving the rate equation
- evidence for mechanism
- iodine clock
- multi step mechanisms
- orders and molecularity
- rate against concentration graphs
Using tangents and initial rate in the exam
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