## State function vs not state function

$\Delta U=q+w$

Rebecca Chen 3F
Posts: 32
Joined: Fri Sep 25, 2015 3:00 am

### State function vs not state function

Hi! I'm still a bit confused as to what a state function is. Also, what is the importance of something being a state function, and (like on page 25 of the course reader), how does this relate to deltaU (a state function) = q + w (not state functions)?

Chem_Mod
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### Re: State function vs not state function

A state function is something whose difference can be defined between any two points. The path taken to get from one point to the other does not matter. You can think of deltaU as being a state function because it is directly related to the temperature. However, the ways in which it can change depend on the path.

704628249
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Joined: Fri Sep 25, 2015 3:00 am

### Re: State function vs not state function

A state function does not depend on the path taken. For example, work is not a state function because the amount of work done does depend on the path that you take, not just the initial and final values.