Practice question · Multiple choice
Diamond converts to graphite with at room temperature, yet diamonds do not visibly change. What does this show?
Hints
- Separate what thermodynamics predicts from what kinetics controls.
- A large activation barrier can make a spontaneous reaction immeasurably slow.
Show the answer
A. Spontaneity says nothing about rate
Why
Thermodynamics says the conversion can happen; kinetics says how fast. An enormous activation barrier keeps the rate effectively zero, so a genuinely spontaneous process takes geological time. A barrier affects rate, not .
Practise Gibbs Free Energy and Spontaneity
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