## sign of entropy

Volume: $\Delta S = nR\ln \frac{V_{2}}{V_{1}}$
Temperature: $\Delta S = nC\ln \frac{T_{2}}{T_{1}}$

Jack Papciak 2F
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### sign of entropy

How do I know whether the entropy has a "+" or a "-"?

Grace Boyd 2F
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### Re: sign of entropy

As Dr. Lavelle explained today in lecture, the sign of entropy depends on the direction of heat flow. If the system loses heat, the entropy will have a negative sign in front of it. If the surroundings gain heat, the entropy will have a positive sign. I hope this helps!

Alyssa Pelak 1J
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### Re: sign of entropy

Additionally, entropy is positive when the reaction spontaneous. It means that the system has more possible states. Entropy is negative when the system has less possible states.

Lauren Seidl 1D
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### Re: sign of entropy

Also, if delta entropy equals zero then the reaction is at equilibrium.

Leanne Wong 1H
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### Re: sign of entropy

You determine the sign of entropy by the direction of heat flow.

RohanGupta1G
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### Re: sign of entropy

Direction of heat flow determines the sign as well as whether or not the reaction is spontaneous.

Jingyi Li 2C
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### Re: sign of entropy

The sign of entropy indicates the direction of heat flow.

Amanda Wu 2C
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### Re: sign of entropy

The sign of entropy is indicative of the heat flow in or out of the system. A system in which heat flows out to the surroundings will have a negative entropy whereas a system in which heat flows in from the surroundings will have a positive entropy.

Josh Moy 1H
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### Re: sign of entropy

sign of entropy depends on flow of heat

melissa carey 1f
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### Re: sign of entropy

Additionally, during a process of expansion entropy increases as there are more possible states.

JamesAntonios 1E
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### Re: sign of entropy

Jack Papciak 2F wrote:How do I know whether the entropy has a "+" or a "-"?

It depends on the the ratio of final to initial temperature, volume, and/or pressure. You can logically think about by analyzing whether the number of microstates is increasing or decreasing, which can give an indication to what the sign should be.

Luke Bricca 1H
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### Re: sign of entropy

Additionally, in connection with Gibbs free energy, if the sign of the delta G is negative, the reaction is spontaneous and favorable.