## R Constant

805383532
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Joined: Thu Jul 11, 2019 12:16 am

### R Constant

How do we know which R constant to use in calculation?

Kimberly Koo 2I
Posts: 99
Joined: Sat Aug 17, 2019 12:17 am

### Re: R Constant

R is the universal gas constant, which is 0.082 L.atm/mol.K

805097738
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Joined: Wed Sep 18, 2019 12:20 am

### Re: R Constant

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

Robert Tran 1B
Posts: 118
Joined: Thu Jul 11, 2019 12:15 am

### Re: R Constant

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.

Jared Khoo 1G
Posts: 107
Joined: Wed Sep 18, 2019 12:16 am

### Re: R Constant

Use the R constant that uses the appropriate unit of pressure.

105335337
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Joined: Sat Aug 24, 2019 12:15 am

### Re: R Constant

R is the universal gas constant and has the units of the other variables (L, atm, etc...)

Veronica Lu 2H
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Been upvoted: 1 time

### Re: R Constant

R is usually 0.082- it may also be on the formula sheet

Trent Yamamoto 2J
Posts: 111
Joined: Sat Aug 17, 2019 12:18 am

### Re: R Constant

The R values are different depending on the temperature used in the reaction