AP Chemistry / Unit 9: Thermodynamics and Electrochemistry
9.4 Thermodynamic and Kinetic Control
Notes
A favorable reaction ($\Delta G<0$) can still be very slow if $E_a$ is high. That's kinetic control.
- Diamond turning into graphite is favorable but extremely slow.
Practice
Diamond → graphite has $\Delta G<0$, but diamonds last. Why?
Kinetically controlled.
A catalyst can make a favorable reaction:
Lowers $E_a$ only.
Thermodynamics tells you:
Kinetics is separate.
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