Question about state functions

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Cecile Riviere-Cazaux 2A
Posts: 11
Joined: Fri Jul 15, 2016 3:00 am

Question about state functions

Postby Cecile Riviere-Cazaux 2A » Wed Jan 18, 2017 9:01 pm

Why and how can internal energy be a state function when it is composed of two path (non-state) functions? (U = q+w)

William Shu 1G
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Joined: Wed Sep 21, 2016 2:56 pm

Re: Question about state functions

Postby William Shu 1G » Wed Jan 18, 2017 9:47 pm

How I understand it is that internal energy is simply the value of energy in the system at any given point in time and it doesn't depend on fluctuation, only on final and initial values. Heat and work may be how it gets there, but mathematically internal energy still remains as a state function. I hope this helps!

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Re: Question about state functions

Postby Chem_Mod » Thu Jan 19, 2017 8:06 pm

Hey Cecile! Another way to understand this is that energy can be distributed through work and heat. Let us think that you go from one state of internal energy to another state. Depending on how you get there, there will be different amounts of heat and work .

Your energy states will be the same, but the amount of heat and work used/given can be different.

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