transition state
What transition state means in Chemistry A-Level, as defined for AQA, OCR.
Definitions of transition state
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Reference: AQA
The arrangement partway through the reaction where old bonds are stretched and new ones are only partly formed and the potential energy is at a maximum.
The peak on an enthalpy profile diagram, representing the state at the maximum enthalpy along the route.
Topics that use transition state
- Collision theory (AQA A-Level)
- Enthalpy changes (OCR A-Level)
Related terms
- Activation energy
- ∆H of combustion
- ∆H of formation
- Approximate estimate
- Average bond enthalpy
- Averaging over gaseous compounds
- Bond breaking and bond making
- Bond enthalpy
Using transition state in the exam
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