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### R Constant

Posted: Sun Jan 19, 2020 11:24 am
How do we know which R constant to use in calculation?

### Re: R Constant

Posted: Sun Jan 19, 2020 11:53 am
R is the universal gas constant, which is 0.082 L.atm/mol.K

### Re: R Constant

Posted: Sun Jan 19, 2020 12:16 pm
Kimberly Koo 2I wrote:R is the universal gas constant, which is 0.082 L.atm/mol.K

there are different R constants for different units though

### Re: R Constant

Posted: Sun Jan 19, 2020 12:55 pm
You should use the R constant that has units that cancel out with the other units in the equation. For example, in PV=nRT, we use 0.08206 (L*atm)/(mol*K) because it cancels with the pressure, volume, moles, and temperature.

### Re: R Constant

Posted: Sun Jan 19, 2020 1:21 pm
Use the R constant that uses the appropriate unit of pressure.

### Re: R Constant

Posted: Sun Jan 19, 2020 1:55 pm
R is the universal gas constant and has the units of the other variables (L, atm, etc...)

### Re: R Constant

Posted: Sun Jan 19, 2020 6:29 pm
R is usually 0.082- it may also be on the formula sheet

### Re: R Constant

Posted: Sun Jan 19, 2020 9:31 pm
The R values are different depending on the temperature used in the reaction