State Functions and Non-State Functions

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Nicole Gamboa 2M
Posts: 21
Joined: Wed Sep 21, 2016 2:56 pm

State Functions and Non-State Functions

Postby Nicole Gamboa 2M » Fri Jan 13, 2017 4:17 pm

Hi All,
Could someone possibly explain to me why state functions are additive and non-state functions aren't? I understand that state functions aren't dependent on the path taken and that you only need to look at the final and initial values but I still don't quite understand how that affects whether or not it can be added. If you had the details of two non-state functions would you be able to add them as well or is it still not possible?
Thanks!

Elias Ruben 1O
Posts: 47
Joined: Wed Sep 21, 2016 2:56 pm

Re: State Functions and Non-State Functions

Postby Elias Ruben 1O » Fri Jan 13, 2017 8:36 pm

Since only the initial and final values matter for a state function, you can calculate exactly how much change there was by subtracting the initial value from the final value. If you do this for each step of a multi-step reaction, you can add them to find the total change of the entire reaction. Non-state functions are not like this because they can vary in value despite having the same endpoints. I do not exactly know whether or not you can add non-state function values, but I think you can't because the path it takes causes them to have different values.

nikita bhat 2D
Posts: 29
Joined: Wed Sep 21, 2016 2:59 pm

Re: State Functions and Non-State Functions

Postby nikita bhat 2D » Sat Jan 14, 2017 3:45 am

As the previous person stated, non-state functions (such as work and energy) do require more information than just the initial and final position. Say there were four people. Two of them went straight to school from their home, while the other two went half way to school, realized they forgot something, returned home and then went to school. Their final destinations were the same, but when comparing how much work was put in, we would need more information than just the initial and final destination to calculate.


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