Question 1

What value of R should I use with atm and litres?

Accepted Answer

R = 0.082057 L·atm/(mol·K). With kPa and litres use 8.314 L·kPa/(mol·K), which is the same number as J/(mol·K).

Question 2

Does the ideal gas law depend on which gas it is?

Accepted Answer

No. For an ideal gas only the number of moles matters, not the type of molecule. The identity of the gas enters only when you convert moles to mass.

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