Spontaneous with Temperature Increase?
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Spontaneous with Temperature Increase?
Can a nonspontaneous process with a positive deltaS become spontaneous if the temperature is increased (assuming that deltaH and deltaS are both independent of temperature)?
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Re: Spontaneous with Temperature Increase?
Yes, when delta H is positive and delta S is positive, it will be spontaneous at high temperatures and nonspontaneous at low temperatures.
This is because when delta S is positive, -T Delta S will be negative. If the T in the equation is large enough, then the whole combined -T Delta S can be greater than the delta H, making the Delta G negative, making it spontaneous.
Hope this helps correct me if I'm wrong.
This is because when delta S is positive, -T Delta S will be negative. If the T in the equation is large enough, then the whole combined -T Delta S can be greater than the delta H, making the Delta G negative, making it spontaneous.
Hope this helps correct me if I'm wrong.
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- Posts: 64
- Joined: Fri Sep 28, 2018 12:28 am
Re: Spontaneous with Temperature Increase?
The previous statement is correct. For Gibbs free energy to be spontaneous it has to be negative so with a high temperature and positive value of delta S and a positive value of delta H the answer will always be negative of delta G which indicates it's spontaneous. Higher temperature increase does not mean it's always spontaneous however if delta S is a negative value and delta H is a positive value then it will give you a positive value of delta G since it's H - TS. The signs of H and S are important when figuring out whether or not temperature increase indicates if it is spontaneous.
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