Calculating Enthalpy with Atoms, Linear Molecules, and Nonlinear Molecules.

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J Medina 2I
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Joined: Wed Sep 25, 2019 12:17 am

Calculating Enthalpy with Atoms, Linear Molecules, and Nonlinear Molecules.

Postby J Medina 2I » Tue Feb 11, 2020 11:46 pm

What are some examples of monatomic gases where we will have to calculate enthalpy with Cv,m as 3/2 R? Will most calculations for with Cv,m use the values associated with Linear molecules (5/2 R) and Nonlinear molecules (3 R)?

Micah3J
Posts: 100
Joined: Tue Oct 08, 2019 12:16 am

Re: Calculating Enthalpy with Atoms, Linear Molecules, and Nonlinear Molecules.

Postby Micah3J » Wed Feb 12, 2020 12:22 am

Yes can someone please go over when we use the 5/2R and the 3/2R? I still don't quite get when to use them and why to use them

Long Luong 2H
Posts: 51
Joined: Thu Sep 19, 2019 12:16 am

Re: Calculating Enthalpy with Atoms, Linear Molecules, and Nonlinear Molecules.

Postby Long Luong 2H » Wed Feb 12, 2020 1:33 am

The monatomic gases where we use (-)R are for when calculating the heat capacity of ideal gases so everything on the right side of the periodic table. You’d use 3/2R for monatomic ideal gases at constant volume. You’d use 5/2R for diatomic ideal gases at constant volume.


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