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### Ideal gas constant R

Posted: Mon Feb 04, 2019 5:02 pm
When do I plug in the ideal gas constant, R, as 0.0825, and when do I plug it in as 8.314?
Not sure when to use which!

### Re: Ideal gas constant R

Posted: Mon Feb 04, 2019 6:06 pm
Look at the units you are dealing with, the constants have different units. So if you don't know try looking at what units you are using and comparing them to the units of the gas constants.

### Re: Ideal gas constant R

Posted: Mon Feb 04, 2019 10:49 pm
I think it just depends on which units you are working with: R = 0.08206 L x atm x K^-1 x mol ^-1 and R = 8.314 J x K^-1 x mol^-1.

### Re: Ideal gas constant R

Posted: Tue Feb 05, 2019 11:08 am
The units for the small constant given above are atm L per mol K and the other constant is J per mol K, since the mol K in the denominator is consistent, it depends on whether you are using pressure and volume( atm and L) or energy (J or kJ) in the overall mathematic expression.

### Re: Ideal gas constant R

Posted: Tue Feb 05, 2019 6:32 pm
Thank you for the responses!

### Re: Ideal gas constant R

Posted: Wed Feb 06, 2019 11:28 pm
That depends on the units that you are given and are working with.

### Re: Ideal gas constant R

Posted: Thu Feb 07, 2019 11:54 am
Depends on the units! L or J

### Re: Ideal gas constant R

Posted: Sat Mar 16, 2019 1:03 pm
just look at the units and see which one to use

### Re: Ideal gas constant R

Posted: Sat Mar 16, 2019 6:56 pm
depends on the units in the question

### Re: Ideal gas constant R

Posted: Sat Mar 16, 2019 7:40 pm
Yeah, it depends on the question and what units you would need to be able to cancel out

### Re: Ideal gas constant R

Posted: Wed Jan 08, 2020 10:25 pm
It depends if the pressure given is in atm or pascals