Equation for a non-state property?

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Wilson Yeh 1L
Posts: 42
Joined: Fri Sep 29, 2017 7:06 am

Equation for a non-state property?

Postby Wilson Yeh 1L » Wed Jan 10, 2018 10:12 pm

So I know that a state property is not dependent on path taken, but rather just final - initial. However, for a non-state property like work and heat, what would be the equation to solve for it?

Anna Okabe
Posts: 30
Joined: Fri Sep 29, 2017 7:06 am

Re: Equation for a non-state property?

Postby Anna Okabe » Wed Jan 10, 2018 10:14 pm

In a sense it is like finding the total distance traveled by a particle. You add up all the distances (changes) it undergoes and add them together, disregarding negatives.

Mia Navarro 1D
Posts: 52
Joined: Fri Sep 29, 2017 7:04 am

Re: Equation for a non-state property?

Postby Mia Navarro 1D » Wed Jan 10, 2018 11:03 pm

The sum of the two non-state properties, work and heat, creates an equation that is a state property. Each of the two is dependent on the process of achieving the final from the initial, making the result not constant.

Beza Ayalew 1I
Posts: 58
Joined: Fri Sep 29, 2017 7:07 am

Re: Equation for a non-state property?

Postby Beza Ayalew 1I » Thu Jan 11, 2018 12:29 am

I think Wilson Yeh wants to know of there is a standard equation that can be applied to situations involving heat or other not state properties that we will have to know? or is the value subjective depending on the situation?

Kyle Sheu 1C
Posts: 87
Joined: Fri Jun 23, 2017 11:39 am

Re: Equation for a non-state property?

Postby Kyle Sheu 1C » Thu Jan 11, 2018 2:16 am

For expansion work under constant external pressure, you can use the eq. w = -Pexternal * deltaV to calculate the work done by the system. There's also a table somewhere in the beginning of Chapter 8, which if I remember correctly, lists various types of work.

As for heat, when pressure is constant, q = delta H


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