When doing calculations, should pressure be in atm or Pa?

AI Thread Summary
When performing calculations involving pressure, it is recommended to use Pascals (Pa) for consistency, especially when calculating work in joules. The ideal gas law requires adjusting constants, such as the gas constant R, to match the chosen units. Using consistent units, such as pressure in Pa and volume in cubic meters, simplifies calculations. It is emphasized to minimize conversions to avoid errors. Overall, maintaining uniformity in units ensures accurate results in calculations.
Lee
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When doing calculations, should pressure be in atm or Pa? (looking for answers in joules)
 
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Doesn't matter AFAIK as long as you adjust the constants for example R in PV=nRT.
 
Good'o. I just wanted to double check.
 
Use Pascals. P = F / A, Force is usually given in Newtons amd 1 Pa = 1 Nm^-2.

edit: should read the thread title, good practice anyway :).
 
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all you need is to have is consistant units.
pressure in Pa, volume in cubic meters and R = 8.3145 J mol^-1 K^-1
then work will be in joules
 
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Always choose the path with the least number of conversions.

Daniel.
 

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