## R (constant 8.314 or 8.206)

$w=-P\Delta V$
and
$w=-\int_{V_{1}}^{V_{2}}PdV=-nRTln\frac{V_{2}}{V_{1}}$

Quynh Nguyen 2O
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### R (constant 8.314 or 8.206)

How do we know when to use R= 8.314 or R = 8.206?

Chem_Mod
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### Re: R (constant 8.314 or 8.206)

You need to look at the units and see which one matches the rest of the units in the calculation. The units for the following are...
8.314 J/mol.K
8.206 L.atm/mol.K

martha-1I
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### Re: R (constant 8.314 or 8.206)

8.206L.atm/mol.k will usually be used when using the equation PV=NRT because the units will cancel out nicely since pressure will be in atm, volume will be in L, n=mol, and T will be in kelvin.

Chem_Mod
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### Re: R (constant 8.314 or 8.206)

Clarification: R = 0.08206 Latm/molK, not 8.206