R in PV=nRT


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sallina_yehdego 2E
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Joined: Sun Apr 29, 2018 3:00 am

R in PV=nRT

Postby sallina_yehdego 2E » Mon Jan 07, 2019 11:10 pm

What does the R represent in the equation PV=nRT? and what are the units?

Jesse Kuehn 1B
Posts: 40
Joined: Wed Nov 14, 2018 12:23 am

Re: R in PV=nRT

Postby Jesse Kuehn 1B » Mon Jan 07, 2019 11:17 pm

It is the called the gas constant and the SI unit for it is J K^-1 mol^-1

Nathan Tran 4K
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Re: R in PV=nRT

Postby Nathan Tran 4K » Mon Jan 07, 2019 11:57 pm

It's essentially a constant usually equal to 8.315 JK^-1mol^-1. I am sure it will be on our constant sheet.

Matthew Tran 1H
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Joined: Fri Sep 28, 2018 12:16 am

Re: R in PV=nRT

Postby Matthew Tran 1H » Tue Jan 08, 2019 12:05 am

Depending on the units of pressure and volume, R can take on different values. A common example is when you are given P in atm (atmospheres) and V in L (liters). In this case R=0.0821(atm*L)/(mol*K)

JiangJC Dis2K
Posts: 72
Joined: Fri Oct 12, 2018 12:16 am

Re: R in PV=nRT

Postby JiangJC Dis2K » Tue Jan 08, 2019 5:02 pm

R is a constant in the ideal gas law (PV=nRT) and has multiple unit derrivations that can all be found on the equations and constants sheet! So no need to memorize the value or units!

Emily Ng_4C
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Joined: Fri Sep 28, 2018 12:17 am

Re: R in PV=nRT

Postby Emily Ng_4C » Tue Jan 08, 2019 5:22 pm

R is the gas constant and it is important to note that it differs depending on whether atm, torr, or bar is used for the pressure unit.

Felicia1E
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Joined: Fri Sep 28, 2018 12:22 am

Re: R in PV=nRT

Postby Felicia1E » Tue Jan 08, 2019 6:04 pm

Different problems will have different units, so as long as you match the unit to the corresponding R value you should be good. Here is a list with some R values:

0.0821 (atm L)/(mol K)
0.0831 (bar L)/(mol K)
8.314 (J)/(K mol)
62.36 (torr L)/(mol K) or (mmHg L)/(mol K)
1.987 (cal)/ (mol K)

Millicent Navarro 1I
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Re: R in PV=nRT

Postby Millicent Navarro 1I » Mon Jan 14, 2019 2:57 pm

PV=nRT is the Ideal Gas Law equation. To answer your question, the R is the ideal gas law constant and there are varying corresponding values (for the most part, problems will specify which value to use.) Some examples can include bar or atm.

705170809
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Re: R in PV=nRT

Postby 705170809 » Mon Jan 14, 2019 3:10 pm

R is gas constant, but the units can be different like atm, torr, or bar.

Brian Hom 2F
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Re: R in PV=nRT

Postby Brian Hom 2F » Mon Jan 14, 2019 3:19 pm

The ideal gas law is PV = nRT, where n is the number of moles, and R is universal gas constant. The value of R depends on the units involved, but is usually stated with S.I. units as: R = 8.314 J/mol. It is just a constant to use in the equation.

Ahmed Mahmood 4D
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Joined: Fri Sep 28, 2018 12:28 am

Re: R in PV=nRT

Postby Ahmed Mahmood 4D » Mon Jan 14, 2019 9:27 pm

R is a constant known as the gas constant. Its units are represented as Joules . mol^-1 and various other units such as atmospheres.

ran2000
Posts: 66
Joined: Fri Sep 28, 2018 12:15 am

Re: R in PV=nRT

Postby ran2000 » Wed Jan 16, 2019 1:00 pm

R is the ideal gas constant 8.314 J/(K mol)


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