Delta in enthalpy and not entropy

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Rida Ismail 2E
Posts: 139
Joined: Sat Sep 07, 2019 12:16 am

Delta in enthalpy and not entropy

Postby Rida Ismail 2E » Fri Feb 07, 2020 1:24 pm

Can someone explain to me why there is a delta in front of the H and not the S? Dr. Lavelle spoke about this today but I still didn’t quite grasp the information.

MeeraBhagat
Posts: 95
Joined: Sat Aug 24, 2019 12:15 am

Re: Delta in enthalpy and not entropy

Postby MeeraBhagat » Fri Feb 07, 2020 3:17 pm

There is also a delta for the entropy term because entropy is a state function.

Bella Townsend
Posts: 50
Joined: Wed Feb 20, 2019 12:18 am

Re: Delta in enthalpy and not entropy

Postby Bella Townsend » Fri Feb 07, 2020 4:25 pm

you can calculate the change in both enthalpy and entropy. Both enthalpy and entropy are state functions

Katie Kyan 2K
Posts: 106
Joined: Fri Aug 09, 2019 12:16 am
Been upvoted: 1 time

Re: Delta in enthalpy and not entropy

Postby Katie Kyan 2K » Fri Feb 07, 2020 5:35 pm

There is also a delta in front of the entropy as it is a state function meaning that you can subtract its final and initial states.

Matt F
Posts: 100
Joined: Sat Aug 17, 2019 12:17 am

Re: Delta in enthalpy and not entropy

Postby Matt F » Sun Feb 09, 2020 11:17 am

There can be a delta (or change in) for enthalpy or entropy since both are state functions. The one equation where delta isn't used is the Boltzmann equation, S=kBlnW, since it is calculating the entropy of the system for that many energy states as opposed to the change in entropy due to a change in the system (such as volume or temperature)

Daria MacAuslan 1H
Posts: 50
Joined: Sat Aug 17, 2019 12:16 am

Re: Delta in enthalpy and not entropy

Postby Daria MacAuslan 1H » Sun Feb 09, 2020 11:50 am

The delta sign just smbolizes that there is a change in that specific value. Both entropy and enthalpy are state functions, and both of them can have calculated changes in their values.

Ruby Richter 2L
Posts: 103
Joined: Thu Jul 25, 2019 12:17 am

Re: Delta in enthalpy and not entropy

Postby Ruby Richter 2L » Mon Feb 10, 2020 10:16 am

Just for clarification then the only case where entropy would not be calculated as delta is in the Boltzmann equation S=kBlnW?


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