Spontaneity
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Spontaneity
How do I determine if a reaction is spontaneous or non spontaneous? E.g. is water melting spontaneous? How do I think through these different scenarios given?
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Re: Spontaneity
Hello,
Water melting will be spontaneous at its melting point. The scenario has to make clear under what conditions the water is present. The water melting will be spontaneous at 0 Celsius , but it won't be below that temperature. Hope this helped!
Water melting will be spontaneous at its melting point. The scenario has to make clear under what conditions the water is present. The water melting will be spontaneous at 0 Celsius , but it won't be below that temperature. Hope this helped!
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Re: Spontaneity
josephyim1H wrote:How do I determine if a reaction is spontaneous or non spontaneous? E.g. is water melting spontaneous? How do I think through these different scenarios given?
Spontaneous means the Gibbs Free Energy is less than 0 and not spontaneous means Gibbs Free Energy is greater than 0. Ice will melt spontaneously, turning into a liquid when the temperature is greater than 0 degree C. Although changes in pressure change what temps it is spontaneous at though we shouldnt need to know how to apply this.
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Re: Spontaneity
Try to look at the situations given and determine whether or not it'll happen without an input of energy.
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Re: Spontaneity
You can determine the spontaneity of a reaction by calculating delta G using standard reaction gibbs free energy values or by comparing the signs for enthalpy and entropy at fixed temperature values.
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