Enthalpy Equation

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KarineKim2L
Posts: 100
Joined: Fri Aug 30, 2019 12:16 am

Enthalpy Equation

Postby KarineKim2L » Sat Mar 14, 2020 8:12 pm

Where does the equation H=U+PV come from? Was there a derivation?

Ariana Iranmahboub1G
Posts: 114
Joined: Fri Aug 09, 2019 12:17 am

Re: Enthalpy Equation

Postby Ariana Iranmahboub1G » Sat Mar 14, 2020 8:15 pm

It comes from deltaU=w+q which is the same as deltaU=deltaH-P*deltaV. You can rearrange this to be deltaH = deltaU+P*deltaV.

Julie Park 1G
Posts: 100
Joined: Thu Jul 25, 2019 12:15 am

Re: Enthalpy Equation

Postby Julie Park 1G » Sat Mar 14, 2020 8:16 pm

Because ,
,
which can be rearranged as

Indy Bui 1l
Posts: 99
Joined: Sat Sep 07, 2019 12:19 am

Re: Enthalpy Equation

Postby Indy Bui 1l » Sat Mar 14, 2020 8:19 pm

The derivation is:
deltaU = w + q
w= deltaH
q=-P*deltaV
so,
deltaU=deltaH-P*deltaV
which you can rearrange as:
H=U+PV


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