Cv vs Cp

Volume:
Temperature:

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Karina Kong 2H
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Cv vs Cp

Postby Karina Kong 2H » Thu Feb 13, 2020 5:08 pm

When do we use Cv vs Cp?

LNgo 1G
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Re: Cv vs Cp

Postby LNgo 1G » Thu Feb 13, 2020 5:35 pm

Use Cv when volume is constant and Cp when pressure is constant.

Dina 2k
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Re: Cv vs Cp

Postby Dina 2k » Thu Feb 13, 2020 6:01 pm

the values are usually given to us, unless it's for an ideal gas, in which the equation sheet gives the formula.

Kyle Rex 1K
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Re: Cv vs Cp

Postby Kyle Rex 1K » Thu Feb 13, 2020 10:19 pm

Cv is when there is no change in volume and Cp when there is no change in pressure

Sanjana Munagala_1j
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Re: Cv vs Cp

Postby Sanjana Munagala_1j » Fri Feb 14, 2020 9:51 am

I want to also point out that you use Cv also when solving for an entropy change in a system that has both a volume change and a temperature change. This is because you have to treat the two changes independently. Therefore when calculating the entropy change due to a temperature change, you have to assume that the volume is constant.

Hope that helps!

Astrid Lunde 1I
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Re: Cv vs Cp

Postby Astrid Lunde 1I » Fri Feb 14, 2020 10:00 am

Cv is constant volume and Cp is constant pressure.

ThomasNguyen_Dis1H
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Re: Cv vs Cp

Postby ThomasNguyen_Dis1H » Fri Feb 14, 2020 11:12 am

Cv is at constant volume and Cp is at constant pressure. For most problems, we use Cv so when in doubt use Cv.

Luc Zelissen 1K
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Re: Cv vs Cp

Postby Luc Zelissen 1K » Fri Feb 14, 2020 3:25 pm

Also remember that for Ideal gasses you can use the equation, Cpm = Cvm + R

Jarrett Peyrefitte 2K
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Re: Cv vs Cp

Postby Jarrett Peyrefitte 2K » Fri Feb 14, 2020 4:09 pm

Cv = Constant volume
Cp = Constant pressure

Rhea Shah 2F
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Re: Cv vs Cp

Postby Rhea Shah 2F » Sun Feb 16, 2020 10:14 pm

Cv is used when volume is held constant, and is equal to 3/2R. Cp is used when pressure is held constant and is equal to 5/2R

Natalie Benitez 1E
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Re: Cv vs Cp

Postby Natalie Benitez 1E » Mon Feb 17, 2020 1:50 pm

Cv is used for constant volume and Cp is used for constant pressure.

pmokh14B
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Re: Cv vs Cp

Postby pmokh14B » Mon Feb 17, 2020 4:42 pm

we use Cv when the volume is constant(isochoric) and Cp when pressure is constant (isobaric)

JesseAuLec1Dis1G
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Re: Cv vs Cp

Postby JesseAuLec1Dis1G » Mon Feb 17, 2020 4:46 pm

Cv is used when there's constant volume and Cp is used when there's constant pressure.

Kishan Shah 2G
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Re: Cv vs Cp

Postby Kishan Shah 2G » Mon Feb 17, 2020 5:02 pm

Basically, Cv represents the heat capacity at constant volume, so a bomb calorimeter per say. Cp represents heat capacity at constant pressure, so an irreversible expansion. Cv is 3/2R and Cp is 5/2R

Emil Velasco 1H
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Re: Cv vs Cp

Postby Emil Velasco 1H » Mon Feb 17, 2020 5:25 pm

Cv is constant volume and Cp is constant pressure

kausalya_1k
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Re: Cv vs Cp

Postby kausalya_1k » Tue Feb 18, 2020 12:02 am

we use Cv for when volume is constant (isochoric) and Cp when pressure is constant (isobaric)

Deja Nora
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Re: Cv vs Cp

Postby Deja Nora » Tue Feb 18, 2020 8:25 pm

Cv represents constant volume while Cp represents constant pressure

Anish Natarajan 4G
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Re: Cv vs Cp

Postby Anish Natarajan 4G » Thu Mar 12, 2020 4:28 pm

Generally it will be stated within the parameters of the problem whether or not pressure/volume is constant.


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