Enthalpy vs. Entropy

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Connie2I
Posts: 29
Joined: Fri Sep 29, 2017 7:07 am

Enthalpy vs. Entropy

Postby Connie2I » Thu Feb 01, 2018 10:42 pm

What is the conceptual difference between calculating the standard enthalpy of a phase change vs. the standard entropy of a phase change?

Vivian Nguyen
Posts: 66
Joined: Fri Sep 29, 2017 7:04 am
Been upvoted: 2 times

Re: Enthalpy vs. Entropy

Postby Vivian Nguyen » Thu Feb 01, 2018 11:21 pm

Hello, the standard enthalpy of a phase change is the change in enthalpy required to supply the energy needed to carry out that certain phase change in a specific substance.
Meanwhile, the entropy of a phase change deals with the change in the number of states (disorder) of the substance.

Angel Gomez 1K
Posts: 36
Joined: Fri Sep 29, 2017 7:04 am

Re: Enthalpy vs. Entropy

Postby Angel Gomez 1K » Fri Feb 02, 2018 2:37 am

Would you mind explaining why enthalpy can be measured as an amount altogether but entropy can only be measured by the changes in it?

Marina Georgies 1C
Posts: 30
Joined: Sat Jul 22, 2017 3:00 am

Re: Enthalpy vs. Entropy

Postby Marina Georgies 1C » Fri Feb 02, 2018 9:43 am

Enthalpy can be measured quantitatively because of processes like calorimetry. It is essentially heat, and we use temperature to measure it directly. Entropy is the measure of how disordered a system is, so it is harder to give it a number value, however; the equation S=kblnW allows you to calculate a value for entropy. hope this helps

Warda Sahib 2J
Posts: 29
Joined: Thu Jul 13, 2017 3:00 am

Re: Enthalpy vs. Entropy

Postby Warda Sahib 2J » Sun Feb 04, 2018 9:59 pm

Entropy is a measure of disorder or randomness of a system. Enthalpy is defined as the sum of internal energy of a system and the product of the pressure and volume of the system.


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