Isobaric systems

isochoric/isometric:
isothermal:
isobaric:

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aphung1E
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Isobaric systems

Postby aphung1E » Thu Feb 13, 2020 9:01 am

Which equations do you tend to use when solving for an isobaric system?
Also which values are equal to zero in an isobaric system?

Nathan Nakaguchi 1G
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Re: Isobaric systems

Postby Nathan Nakaguchi 1G » Thu Feb 13, 2020 10:34 am

When a system is isobaric that means that the pressure is constant, which implies that . I think this is all you can assume from this statement. Dr. Lavelle didn't really talk specifically about the terms isobaric and isochoric, so I wouldn't worry too much about it.

Maya Beal Dis 1D
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Re: Isobaric systems

Postby Maya Beal Dis 1D » Thu Feb 13, 2020 10:42 am

Isobaric is constant pressure, isochoric is constant volume, and isothermal is constant temperature.

Max Madrzyk Dis 4G
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Re: Isobaric systems

Postby Max Madrzyk Dis 4G » Thu Feb 13, 2020 10:44 am

Isobaric means constant pressure and when you have a system at constant pressure you can say that delta h=q.

LNgo 1G
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Re: Isobaric systems

Postby LNgo 1G » Thu Feb 13, 2020 12:27 pm

In an isobaric system, pressure is constant, so delta P would equal zero. In this case, work can be calculated using the formula w=-PdeltaV and heat can be calculated using q=deltaH.

Gabriel Ordonez 2K
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Re: Isobaric systems

Postby Gabriel Ordonez 2K » Thu Feb 13, 2020 3:03 pm

Isobaric is constant pressure, isochoric is constant volume, and isothermal is constant temperature. With these conditions, you'll need to match up the right equations with each one. There are reversible and irreversible equations.

Leslie Almaraz 4G
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Re: Isobaric systems

Postby Leslie Almaraz 4G » Thu Feb 13, 2020 7:35 pm

What about an adiabatic system? is there a different equation for that?

Amanda Lin 2I
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Re: Isobaric systems

Postby Amanda Lin 2I » Fri Feb 14, 2020 6:50 pm

For an adiabatic system there is no heat transfer so q=0 and ΔU=w.

Kallista McCarty 1C
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Re: Isobaric systems

Postby Kallista McCarty 1C » Fri Feb 14, 2020 6:53 pm

Isobaric is constant temperature!

Orrin Zhong 4G
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Re: Isobaric systems

Postby Orrin Zhong 4G » Fri Feb 14, 2020 10:17 pm

Isobaric means constant pressure. Under these conditions, h = deltaH, since deltaH is defined at constant pressure. Also, w = -(Pext)(deltaV) since pressure is fixed.

Jacob Motawakel
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Re: Isobaric systems

Postby Jacob Motawakel » Sat Feb 15, 2020 4:06 pm

Isobaric means constant pressure, so at constant pressure q=deltaH, w= -PV.

CMaduno_1L
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Re: Isobaric systems

Postby CMaduno_1L » Sat Feb 15, 2020 7:12 pm

During Lyndon and Matt's Pizza Rolls review session, Matt made a comment that might help with remembering the meaning of isobaric. He emphasized the BAR in isoBARic and compared it to BARometer, which is an instrument used to measure atmospheric pressure. Hope this helps!

Rebekah Alfred 1J
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Re: Isobaric systems

Postby Rebekah Alfred 1J » Sat Feb 15, 2020 7:14 pm

Leslie Almaraz 4G wrote:What about an adiabatic system? is there a different equation for that?

In an adiabatic system, there is no heat transfer (q=0).

CalvinTNguyen2D
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Re: Isobaric systems

Postby CalvinTNguyen2D » Sun Feb 16, 2020 7:01 pm

Isobaric means constant pressure. Isochoric means constant volume. Isothermal means constant temperature.

William Francis 2E
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Re: Isobaric systems

Postby William Francis 2E » Sun Feb 16, 2020 7:23 pm

When pressure is constant, ΔH=q. This is because ΔH=ΔU+PΔV. Since ΔU=q+w, the equation can be rewritten as, ΔH=q+w+PΔV. Since w=-PexΔV, that equation can be rewritten as ΔH=q-PexΔV+PΔV. P=Pex in isobaric conditions so ΔH=q. Therefore, Cp=ΔH/ΔT under these conditions.

Kylie Lim 4G
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Re: Isobaric systems

Postby Kylie Lim 4G » Sun Feb 16, 2020 7:34 pm

For isobaric reactions, pressure is constant. This means that both equations for w can be used, as well as the relationship where delta H = q

KHowe_1D
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Re: Isobaric systems

Postby KHowe_1D » Sun Feb 16, 2020 8:06 pm

Isobaric systems are systems with constant pressure so you would use an equation that works with the variables you are given as long as pressure is constant. A common equation is deltaH = q


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