State Properties: q vs. qp

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Matt_Fontila_2L_Chem14B
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Joined: Fri Sep 29, 2017 7:07 am

State Properties: q vs. qp

Postby Matt_Fontila_2L_Chem14B » Wed Jan 10, 2018 3:18 pm

I'm confused why q is not a state property while qp (heat at constant pressure) is a state property. I know that they are heat and enthalpy, but how do the "paths taken" to get to their final states matter for each?

Jakob von Morgenland 2C
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Re: State Properties: q vs. qp

Postby Jakob von Morgenland 2C » Wed Jan 10, 2018 3:27 pm

I believe it has something to do with the fact that pressure (P) is considered a state property. Because it is dependent on a state property, Qp itself becomes a state property; however, Q itself is not a state property.

Tatiana Hage 2E
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Re: State Properties: q vs. qp

Postby Tatiana Hage 2E » Wed Jan 10, 2018 3:33 pm

Heat is dependent on the path or the way the state of the system changes.

Niyanta Joshi 1F
Posts: 30
Joined: Thu Jul 13, 2017 3:00 am

Re: State Properties: q vs. qp

Postby Niyanta Joshi 1F » Wed Jan 10, 2018 4:16 pm

Work is a state property as it is directly proportional to the object's distance moved against the opposing force and this distance depends on the path taken. Since deltaU = W + q, and work is a state function, it seems that the heat given off must be dependent on the path as well.


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