State Function?

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David Effio 1H
Posts: 38
Joined: Wed Feb 14, 2018 3:01 am

State Function?

Postby David Effio 1H » Sun Jan 27, 2019 12:00 am

I'm a little confused as to what it means that enthalpy is a state function. I understand that we can add and subtract them freely, but I do not understand how that is related to it being a state function.

Noah Cook 3O
Posts: 31
Joined: Fri Sep 28, 2018 12:20 am

Re: State Function?

Postby Noah Cook 3O » Sun Jan 27, 2019 12:06 am

Basically a state function is something that depends only on its current equilibrium state, not on how it got there. So for chemical reactions, this means that we can just add/subtract the overall enthalphies, and don't have to worry about the intermediate steps that a reaction may have gone through to reach equilibrium.

Michael Torres 4I
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Joined: Thu May 10, 2018 3:00 am
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Re: State Function?

Postby Michael Torres 4I » Sun Jan 27, 2019 10:40 am

Adding on to the previous explanation, something that is not a state function would be work. Going from one place to another may done differently, and therefore different amounts of work may be required to get from one place to another. On the other hand, enthalpy has no such possibilities for alternative methods. Rather, because a reaction simply changes enthalpy directly there is no need to take such differences into account. The “how” of something does not matter in the case of enthalpy.

Christopher Anisi 2K
Posts: 30
Joined: Fri Sep 28, 2018 12:21 am

Re: State Function?

Postby Christopher Anisi 2K » Sun Jan 27, 2019 11:44 am

A state function is independent of the previous process paths to go from state A to B. The amount of energy to get from A to B does not matter when dealing with state functions.

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