State functions

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Nhat Anh Cao 1C
Posts: 14
Joined: Fri Sep 25, 2015 3:00 am

State functions

Postby Nhat Anh Cao 1C » Sun Jan 10, 2016 11:39 pm

What are some other examples of state functions?

Chem_Mod
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Re: State functions

Postby Chem_Mod » Mon Jan 11, 2016 9:24 am

Enthalpy, Entropy, Internal Energy, Potential Energy, etc.

Kayti Luu 2B
Posts: 19
Joined: Fri Sep 25, 2015 3:00 am

Re: State functions

Postby Kayti Luu 2B » Mon Jan 11, 2016 10:28 am

I understand that in a state function what matters is the initial and final, not the path that it takes, but why isn't heat a state function when enthalpy and enthalpy is a measurement of heat?

Ronald Yang 2F
Posts: 86
Joined: Fri Sep 25, 2015 3:00 am

Re: State functions

Postby Ronald Yang 2F » Tue Jan 12, 2016 1:31 am

Hey Kayti,

It's because the path heat takes does matter, since heat is a "transfer" of energy. It only exists during a change, not at the beginning and end of a change.

AngelinaArianaAviles3G
Posts: 10
Joined: Fri Sep 25, 2015 3:00 am

Re: State functions

Postby AngelinaArianaAviles3G » Tue Jan 12, 2016 11:48 am

Hi Kayti,
Heat isn't a state function, it is a path function.
While enthalpy refers to the heat transferred or absorbed in a chemical reaction, it is done so at a constant pressure so the only final and initial are held in to account to calculate the enthalpy of a reaction. Enthalpy is a state property because it can be added.

Also, just as a side note, heat and work are considered the non-state functions. And as professor Lavelle stated, enthalpy, entropy, potential energy, etc. are state functions.


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