## Spontaneity

$\Delta S = \frac{q_{rev}}{T}$

Anokhi Patel 2B
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### Spontaneity

What determines whether a reaction is spontaneous or not? Is it based on whether the change in molar Gibbs free energy is positive or negative?

kim 2I
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### Re: Spontaneity

When delta G is negative, the reaction is spontaneous, and when delta G is positive, the reaction is nonspontaneous. However, in terms of potentials differences (E), when the value is postive, the cell reaction is spontaneous, and when the value is negatvie, the cell reaction is nonspontaneous. This is because of the equation deltaG= -nFEcell.

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### Re: Spontaneity

A negative delta G indicates a spontaneous reaction, and a positive delta G indicates a nonspontaneous reaction.

Wendy 1E
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### Re: Spontaneity

If you are observing a galvanic cell, you can also tell if a reaction is spontaneous if E°cell is positive.

Pegah Nasseri 1K
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### Re: Spontaneity

A reaction is spontaneous when $\Delta G< 0$. This is because there is available energy released by the reaction that can used to perform work. Remember that if the change in gibbs free energy of a forward reaction is positive, its reverse reaction can be spontaneous because the change in gibbs free energy of the reverse reaction would be negative. In addition, using the equation $\Delta G= -nFE$, you can conclude that if the cell potential (E) is positive, then the change in gibbs free energy is negative, allowing the reaction to be spontaneous.

Altamash Mahsud 1I
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### Re: Spontaneity

A reaction is spontaneous if the delta G is negative, and it is non spontaneous when the delta G is positive. When talking about electrochemistry, a positive E cell means the reaction is spontaneous, and a negative E cell means the reaction is non spontaneous.

005206171
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### Re: Spontaneity

Spontaneous reactions can be detected by a negative Gibbs free energy and positive potential difference.

Sally Qiu 2E
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### Re: Spontaneity

when delta G is negative it means the reaction is spontaneous

Jialun Chen 4F
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### Re: Spontaneity

In addition to the sign of Gibbs free energy, the sign of cell potential can also serve as an indicator: if Ecell is greater than zero, the reaction is spontaneous, vice versa.

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### Re: Spontaneity

When you have a +E naught , it means that you will get a -deltaG , which means that k>1. A -deltaG is spontaneous.
When you have a -E naught, it means that you will get a +deltaG , which means that k<1. A +deltaG is non spontaneous.

Lizette Noriega 1H
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### Re: Spontaneity

positive cell potential (-E) = negative delta G = spontaneous
negative cell potential (+E) = positive delta G = nonspontaneous

Rida Ismail 2E
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### Re: Spontaneity

The change is delta G needs to be negative

Yailin Romo 4G
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### Re: Spontaneity

For the reaction to be spontaneous, delta G has to be negative