Adding and subtracting properties

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005321227
Posts: 90
Joined: Sat Sep 07, 2019 12:15 am

Adding and subtracting properties

Postby 005321227 » Thu Jan 23, 2020 9:36 am

Can someone please explain why we do final minus initial when doing state properties?

Ally Huang- 1F
Posts: 103
Joined: Thu Jul 25, 2019 12:16 am

Re: Adding and subtracting properties

Postby Ally Huang- 1F » Thu Jan 23, 2020 10:53 am

State properties are not dependent on the path taken to obtain that state. You do final minus initial with state properties because it does not matter the path taken to get to the final state, only the final and initial values matter.

Nathan Nakaguchi 1G
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Re: Adding and subtracting properties

Postby Nathan Nakaguchi 1G » Thu Jan 23, 2020 11:34 am

State properties only depend on the final and initial states. They only care about the destinations not the journey.

So for deltas like enthalpy (which is state dependent), to find it you do: Final state value - Initial state value. State dependent properties are only involved with total changes from start to finish, not in between.

Abby Soriano 1J
Posts: 103
Joined: Sat Aug 24, 2019 12:16 am

Re: Adding and subtracting properties

Postby Abby Soriano 1J » Thu Jan 23, 2020 12:08 pm

We can add the final and initial values for state properties since we don't care about what goes on in the middle of the process. Work and energy are different in which we want to look at how much is being used and wasted on the journey.

ShastaB4C
Posts: 100
Joined: Thu Sep 26, 2019 12:18 am

Re: Adding and subtracting properties

Postby ShastaB4C » Thu Jan 23, 2020 12:57 pm

Can someone give me an example of a property that is dependent on the path taken besides work?

Kayli Choy 2F
Posts: 100
Joined: Sat Aug 24, 2019 12:17 am

Re: Adding and subtracting properties

Postby Kayli Choy 2F » Thu Jan 23, 2020 2:22 pm

ShastaB4C wrote:Can someone give me an example of a property that is dependent on the path taken besides work?


Heat is also a path function because the energy transferred as heat depends on how that change occurred.

Uisa_Manumaleuna_3E
Posts: 60
Joined: Wed Sep 21, 2016 2:56 pm

Re: Adding and subtracting properties

Postby Uisa_Manumaleuna_3E » Thu Jan 23, 2020 7:12 pm

State properties, as said above, are not dependent on the "in between"; rather, we only focus on the initial and final measurements to make calculations and assumption.

State properties include energy, pressure, volume, temperature, density and heat capacity

Non state properties (or properties that are dependent on the "in between") include work and heat.


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