pv nrt r constants
universal constant R another question!?
Thanks for the replies. Why then does R have nothing to do with STP yet it can be derived (calculated from it)? Also how does R allow for units to be cancelled out in Pv=nRT. Please show an example
I haven’t seen your other questions but R does have something to do with STP:
At STP (0 degrees C, 1 atm pressure) an Ideal Gas (and many real gases) obey the Ideal Gas Law which you cite.
R is a physical constant. I’m used to expressing this as 0.08205 lit-atm/mole-K. Notice the units in its dimensions have unit for the other variables in the Ideal Gas Law
Let’s say you’re calculating the number of liters that one mole of gas would have at STP, your calculation would be:
V = nRT/P
= (1 moles)*(0.08205 lit-atm/mole-K)*(273K)/(1 atm)
You can see that the units of R “cancel out” the units of the other variables on the righthand side of the equation leaving only the units of volume (lit) which is what the volume on the left should be.
I hope this helps
PV=nRT to Metric- ChalkTalklast
