Spontaneous Reactions

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Khachik_Hmayakyan_2E
Posts: 25
Joined: Sat Jul 09, 2016 3:00 am

Spontaneous Reactions

Postby Khachik_Hmayakyan_2E » Sun Jan 29, 2017 4:25 pm

Is there work being done by or on the system if the reaction is sponanteous?

Sean_Yue_1E
Posts: 9
Joined: Wed Nov 18, 2015 3:00 am
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Re: Spontaneous Reactions

Postby Sean_Yue_1E » Sun Jan 29, 2017 4:56 pm

A spontaneous chemical reaction is exergonic when it is spontaneous. This means that work is being done by the system on its surroundings, and the ΔG in this case from ΔG = ΔH = TΔS will be negative.

Laura_funes_1j
Posts: 8
Joined: Mon Jan 26, 2015 2:17 pm

Re: Spontaneous Reactions

Postby Laura_funes_1j » Sun Jan 29, 2017 5:03 pm

Spontaneous reactions are usually exergonic, meaning that energy flows from the system to the surroundings. The energy released, free energy, can be used to do work.

LeontyneHenderson2E
Posts: 16
Joined: Wed Sep 21, 2016 2:57 pm

Re: Spontaneous Reactions

Postby LeontyneHenderson2E » Fri Feb 10, 2017 4:09 pm

Are there rules for enthalpy and entropy when it comes to whether a reaction is spontaneous or not?

Stephanie_Younan_3D
Posts: 11
Joined: Sat Jul 09, 2016 3:00 am

Re: Spontaneous Reactions

Postby Stephanie_Younan_3D » Fri Feb 10, 2017 8:44 pm

There are rules for enthalpy and entropy, but it depends on the conditions:
If delta H is + and delta S is -, then delta G is nonspontaneous at ALL temperatures
If delta H is - and delta S is -, then delta G is spontaneous at low temperatures
If delta H is + and delta S is +, then delta G is spontaneous at high temperatures
If delta H is - and delta S is +, then delta G is spontaneous at ALL temperatures


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