Quick Conceptual question






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Jennifer Torres 2L
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Joined: Tue Nov 14, 2017 3:01 am

Quick Conceptual question

Postby Jennifer Torres 2L » Tue Feb 05, 2019 5:47 pm

Could someone explain the difference between enthalpy and entropy? And what equations would be used in each case?

Vicky Lu 1L
Posts: 60
Joined: Fri Sep 28, 2018 12:18 am

Re: Quick Conceptual question

Postby Vicky Lu 1L » Tue Feb 05, 2019 8:32 pm

Enthalpy (H) refers to the heat in the system while entropy (S) can be thought of as the disorder of the system. They are connected by delta G = delta H - T*delta S. For enthalpy, use the 3 methods: Standard Enthalpy of Formation, Bond Enthalpy, and Hess's Law. In Entropy, changes in volume would use delta s = nRln(Vf/Vi), changes in pressure would use delta s = nRln(Pi/Pf), and changes in temperature uses delta s = nCspln(Tf/Ti).

Sophie Roberts 1E
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Joined: Fri Sep 28, 2018 12:17 am

Re: Quick Conceptual question

Postby Sophie Roberts 1E » Sun Feb 10, 2019 3:24 pm

In addition to what was said above, entropy can determine if a reaction is spontaneous (favorable) or not but Enthalpy cannot determine this.

Total entropy >>0 - Spontaneous
Total entropy <<0 - Non spontaneous

Philipp_V_Dis1K
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Joined: Fri Sep 28, 2018 12:20 am

Re: Quick Conceptual question

Postby Philipp_V_Dis1K » Fri Feb 15, 2019 12:06 pm

Entropy is the amount of chaos in the system, while enthalpy is the heat released

Cynthia Aragon 1B
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Joined: Mon Apr 09, 2018 1:38 pm

Re: Quick Conceptual question

Postby Cynthia Aragon 1B » Fri Feb 15, 2019 12:29 pm

Enthalpy refers to the measure of total heat content in a thermodynamic system under constant pressure and is denoted by the symbol H. Entropy refers to the measure of the level of disorder and is denoted by the symbol S. Entropy is calculated in terms of change Delta S = q/T where q is the heat content and T is the temperature.

LedaKnowles2E
Posts: 62
Joined: Fri Sep 28, 2018 12:27 am

Re: Quick Conceptual question

Postby LedaKnowles2E » Fri Feb 15, 2019 1:20 pm

Enthalpy is the heat transferred in/out of the system, while entropy is the disorder of the system (how many possible positions, vibrations, etc).

LaurenJuul_1B
Posts: 65
Joined: Fri Sep 28, 2018 12:17 am

Re: Quick Conceptual question

Postby LaurenJuul_1B » Fri Feb 15, 2019 1:24 pm

enthalpy is the heat released from the system and entropy is the amount of disorder of the system

904914909
Posts: 60
Joined: Fri Sep 28, 2018 12:26 am

Re: Quick Conceptual question

Postby 904914909 » Fri Feb 15, 2019 1:42 pm

Enthalpy is a measure of heat transfer while entropy is a measure of disorder in a system


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