Ideal Gas Equation: Calculating R in PV=nRT

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The discussion focuses on determining the appropriate value of the gas constant R for the ideal gas equation PV=nRT when using specific units: pressure in bar, volume in cubic meters, moles in mol, and temperature in Kelvin. Participants clarify that R must be adjusted according to the units used, with one suggesting starting with R = 0.0821 L·atm/(mol·K) and converting it to match the given units. A user expresses confusion over the lack of explicit units in the problem statement, questioning if there was an error. The conversation emphasizes the importance of understanding unit conversions in gas law calculations. Overall, the thread provides guidance on how to approach the problem and highlights the need for clarity in unit specifications.
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Homework Statement



The ideal gas equation, PV=nRT, may have the following units:
P is given in bar (bar)
V is given in m3 (cubic meters)
N is given in mol (moles)
T is given in K (kelvin)

Which value of R would you use for the calculation if you were using the above units for the other variables in the calculation?

Homework Equations



Dont have any.

The Attempt at a Solution



I have no attempt at the solution as i honestly do not understand how to come to a conclusion. I am a first year university student, having just started a degree in Biochemistry - and i have three basic chemistry modules to complete before i can get onto Biochemistry.

This being a career change for me at age 34, and not having done science in school, i am really stuck and have been battling on this question for a week now.

Any help would be greatly appreciated - just an explanation of where to start would be of great help.

Thanks!
 
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Solve for R - and replace given symbols (P, V, n, T) with units.

--
methods
 
The gas constant's value is determined by its units. If you alter the units you need to alter the value of the constant also. The gas constant is joules per (kelvin x mol). If you multiply pressure in pascals by volume in metres you get joules. Since your volume is in metres already, you need to find out the relationship between pascals and bar.
At least, I think that's correct...
 
Borek said:
Solve for R - and replace given symbols (P, V, n, T) with units.
You beat me Borek!
Is what I said reliable?
 
Thank you for the response :)

Problem is - the question is exactly as i typed it. There are no units given, at all. Hence why i am stumped :/

Have they perhaps made a mistake, or am i really being clueless?
 
Dodabby said:
P is given in bar (bar)
V is given in m3 (cubic meters)
N is given in mol (moles)
T is given in K (kelvin)

No units?

--
methods
 
You could start with R = 0.0821 \frac{L\cdot atm}{mol\cdot K} and convert the pressure and volume to the other units.
 

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