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Postby Dakota_Campbell_1C » Thu Jan 31, 2019 9:59 pm

What does exergonic mean in terms of Gibbs free energy. How does it determine spontaneity?

Jim Brown 14B Lec1
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Re: Gibbs

Postby Jim Brown 14B Lec1 » Thu Jan 31, 2019 10:02 pm

If Gibbs Free Energy is negative, the reaction is spontaneous (exergonic). If Gibbs is positive, the reaction is nonspontaneous (endergonic).
The change in Gibbs is equal to the change in enthalpy minus the change in entropy times T.

Nicole Lee 4E
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Re: Gibbs

Postby Nicole Lee 4E » Thu Jan 31, 2019 10:47 pm

Exergonic means that no work needs to be done for the reaction to occur. So the reaction is spontaneous.

Matthew Mar 1J
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Re: Gibbs

Postby Matthew Mar 1J » Sat Feb 02, 2019 8:53 pm

Also, exergonic reactions release energy while endergonic reactions absorb energy, so you can think of the negative G value as the reaction losing energy and the positive G value as the reaction gaining energy.

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Re: Gibbs

Postby juleschang16 » Sat Feb 02, 2019 9:08 pm

The Gibbs free energy graph shows whether or not a reaction is spontaneous-- whether it is exergonic or endergonic. ... Generally, all reactions want to go to a lower energy state, thus a negative change is favored. Negative ΔG indicates that the reaction is exergonic and spontaneous.

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Re: Gibbs

Postby 805132275 » Sun Feb 03, 2019 1:57 pm

Gibbs free energy is essentially a measure of how much work/energy is available to be done by a system. When you have a (-) Gibbs free energy, the reaction is exothermic and essentially spontaneous. When the value is (+), the reaction is endothermic and non-spontaneous. By spontaneity, it means that the reaction simply goes forward, not that it goes on its own without any input of energy.

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