## Spontaneous?

$\Delta G^{\circ} = -nFE_{cell}^{\circ}$

Valeria Viera 1B
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### Spontaneous?

How do you know if delta S, H, or G are spontaneous?

Jaqueline Monreal 2L
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### Re: Spontaneous?

they are usually spontaneous if they're values are negative, meaning they are releasing energy

Dhwani Krishnan 1G
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### Re: Spontaneous?

Enthalpy doesn't really show spontaneity, except that exothermic reactions are generally spontaneous because delta S is usually positive for these reactions.

A positive entropy generally indicates a spontaneous process, but only with a negative delta G can you be sure.

Ariel Cheng 2I
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### Re: Spontaneous?

I think the only way to be sure of spontaneity is when ΔG is negative (when ΔH −TΔS is negative) though I could be wrong.

Sheridan Slaterbeck 1J
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### Re: Spontaneous?

It is spontaneous if delta G is negative, if (-TdeltaS) is negative, if deltaS is positive, and if delta H is negative
delta G = deltaH -TdeltaS

Sheridan Slaterbeck 1J
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### Re: Spontaneous?

When delta G is negative it is exergonic and when it is positive it is endergonic
when delta H is negative it is exothermic and when it is positive it is endothermic.

505211599
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### Re: Spontaneous?

You can only know for sure if a process is spontaneous if delta G is negative.

Mariana Fuentes 1L
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### Re: Spontaneous?

if delta s is positive the process will be spontaneous.
if delta g is negative then it is exergonic meaning that it is spontaneous in the forward direction.
if delta g is greater than 0 it is spontaneous in the reverse direction.
delta h <0 and delta s>0 spontaneous
delta h<0 and delta s spontaneous if temperature is low

Jacob Bershatski 4C
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### Re: Spontaneous?

Enthalpy cannot be used to determine spontaneity. By definition, a negative deltaG means a reaction is spontaneous. A positive deltaS I assume would also be considered spontaneous in most cases according to the Second Law of Thermodynamics.

Aiden Atoori 1C
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### Re: Spontaneous?

You can determine if it’s spontaneous depending on whether delta G is negativeness or not.

isarose0
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### Re: Spontaneous?

if delta G is negative, the reaction is spontaneous, if delta G is positive it is nonspontaneous

AnnaYan_1l
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### Re: Spontaneous?

When delta G is negative, it is spontaneous

Jack DeLeon 1B
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### Re: Spontaneous?

with a negative deltaG, it indicates that the second state of the reaction, in other words the products, are favored so therefore the reaction is spontaneous

Rehan Chinoy 1K
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### Re: Spontaneous?

I think there is some general confusion about what spontaneity is. "Spontaneous" describes a process or reaction, so values of delta H, G, or S themselves cannot be spontaneous, but they can be used to prove spontaneity through the equation Delta G = Delta H - Temp(Delta S). The process is spontaneous when Delta G is negative.