PV = nRT: Understanding Pressure Units in Gas Laws

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In the context of the ideal gas law PV = nRT, the units for pressure (P) depend on the value of the gas constant (R) used. If R is 8.314472 m³·Pa·K⁻¹·mol⁻¹, pressure must be in pascals (Pa) and volume in cubic meters (m³). Conversely, if R is 0.08205784 L·atm·K⁻¹·mol⁻¹, pressure should be in atmospheres (atm) and volume in liters (L). It's essential to match the units of pressure and volume with the specific gas constant to ensure accurate calculations. Understanding these unit conversions is crucial for applying the ideal gas law correctly.
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Quick Question...Test at 8 am!

When using PV = nRT does P have to be in atm? Or is it Pa?
 
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BuBbLeS01 said:
When using PV = nRT does P have to be in atm? Or is it Pa?

depends on the R you're using...

if you learned
R = 8.314472 m3·Pa·K-1·mol-1

then you need to use pressure in Pa. and volume needs to be in m^3. which R did you learn?

if you learned
R = 0.08205784 L·atm·K-1·mol-1

then you need to use pressure in atm. and volume needs to be in L.

have a look at the R using different units:

http://en.wikipedia.org/wiki/Ideal_gas_law
 
oh ok thanks
 
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