When to use C=5/2R or C=3/2R

isochoric/isometric:
isothermal:
isobaric:

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Chem_Mod
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When to use C=5/2R or C=3/2R

Postby Chem_Mod » Sun Oct 02, 2011 5:32 pm

I was wondering when to use for pressure and for volume.

Chem_Mod
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Re: When to use C=5/2R or C=3/2R

Postby Chem_Mod » Sun Oct 02, 2011 8:01 pm

and are the heat capacities for monatomic ideal gases.

Taylor Pio 3H
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Re: When to use C=5/2R or C=3/2R

Postby Taylor Pio 3H » Tue Jan 12, 2016 9:55 pm

What does the R stand for in this equation?

Stefanie Bui 1J
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Re: When to use C=5/2R or C=3/2R

Postby Stefanie Bui 1J » Tue Jan 12, 2016 11:02 pm

In this equation, R stands for the constant 8.3145 J*K-1*mol-1.

Joyce Zhang 2D
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Re: When to use C=5/2R or C=3/2R

Postby Joyce Zhang 2D » Sat Mar 18, 2017 8:01 pm

What about diatomic molecules?

Adrian Lim 1G
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Re: When to use C=5/2R or C=3/2R

Postby Adrian Lim 1G » Tue Jan 16, 2018 11:14 pm

R is essentially the gas constant, which is 8.314 J * K^-1 * mol^-1. When we use this constant to find heat (q) with the equation q = m * c * delta t, we need to make sure the m is in moles because the unit of the constant is given per mole.

404982241
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Re: When to use C=5/2R or C=3/2R

Postby 404982241 » Mon Feb 11, 2019 8:48 pm

use the 5/2 when pressure is constant.
use 3/2 when volume is constant.

a great example is problem 8.31 in the 6th edition

Melody P 2B
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Re: When to use C=5/2R or C=3/2R

Postby Melody P 2B » Mon Feb 11, 2019 9:01 pm

404982241 wrote:use the 5/2 when pressure is constant.
use 3/2 when volume is constant.

a great example is problem 8.31 in the 6th edition


Would these only be used when working with an ideal gas?


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