Practice question · True or false
A reaction with a positive enthalpy change can still be spontaneous.
Hints
- Consider what happens when the entropy term is large and positive.
- At high enough temperature, T times dS can exceed dH.
Show the answer
True
Why
True, an endothermic reaction becomes spontaneous once exceeds . Dissolving ammonium nitrate absorbs heat and gets cold, yet happens readily because the entropy gain is large.
Practise Gibbs Free Energy and Spontaneity
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