5/2R vs 3/2R


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Briana Yik 1H
Posts: 30
Joined: Fri Sep 28, 2018 12:20 am

5/2R vs 3/2R

Postby Briana Yik 1H » Tue Feb 19, 2019 11:06 pm

how do we know when to use 5/2R versus 3/2R?

lizettelopez1F
Posts: 29
Joined: Fri Sep 28, 2018 12:19 am

Re: 5/2R vs 3/2R

Postby lizettelopez1F » Tue Feb 19, 2019 11:32 pm

Cp=5/2r is used when you need to find the heat capacity of an ideal gas with a constant pressure. Cv=3/2R is used when you need to find the heat capacity of an ideal gas with a constant volume

KatrinaPho_2I
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Joined: Fri Sep 28, 2018 12:28 am

Re: 5/2R vs 3/2R

Postby KatrinaPho_2I » Wed Feb 20, 2019 4:39 pm

These values only work if you are dealing with monoatomic ideal gases.

abbydouglas1K
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Joined: Fri Sep 28, 2018 12:26 am

Re: 5/2R vs 3/2R

Postby abbydouglas1K » Fri Feb 22, 2019 9:04 am

If the question says that the pressure is being kept constant(Cp) or that the volume is being kept constant (Cv) you will use 5/2R and 3/2R respectively if the molecule in question is a monatomic gas.

Christopher Anisi 2K
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Joined: Fri Sep 28, 2018 12:21 am

Re: 5/2R vs 3/2R

Postby Christopher Anisi 2K » Fri Mar 15, 2019 9:51 pm

For a monoatomic gas under a constant pressure the Cp value is equal to 5/2R however if it is under a constant volume the Cv value is equal to 3/2R.

Morgan Carrington 2H
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Joined: Wed Nov 14, 2018 12:22 am

Re: 5/2R vs 3/2R

Postby Morgan Carrington 2H » Thu Jan 30, 2020 12:10 am

KatrinaPho_2I wrote:These values only work if you are dealing with monoatomic ideal gases.


What does you mean by a monoatomic gas?

Claire_Kim_2F
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Joined: Wed Sep 30, 2020 10:02 pm

Re: 5/2R vs 3/2R

Postby Claire_Kim_2F » Fri Nov 06, 2020 3:15 pm

Monoatomic gases are gases that are noble gases like halogen and other substances.

John Calonia 1D
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Joined: Wed Sep 30, 2020 9:49 pm

Re: 5/2R vs 3/2R

Postby John Calonia 1D » Mon Feb 01, 2021 4:48 pm

What are the different heat capacities involving R of different types of molecules and is the general rule +1 R for constant pressure.

Adrienne Chan 1G
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Joined: Wed Sep 30, 2020 9:40 pm

Re: 5/2R vs 3/2R

Postby Adrienne Chan 1G » Mon Feb 01, 2021 5:13 pm

Monoatomic gases are gases that are noble gases like halogen and other substances.


Almost! Monoatomic gases are gases with only one atom, so it would just be noble gases. Halogens are diatomic gases.


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