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Which produces greater work: reversible or irreversible expansion?
Hmmm... I guess you really have no idea. The general equation for expansion work isdw = -pextdV.In a reversible expansion, pext = pgas (orsimple p). Substituting the ideal gas law,dw = -nRTdV/VUpon integration,w = -nRTln(V2/V1)
http://en.wikipedia.org/wiki/Isothermal_process#Calculation_of_workclinz63 said the stuff I linked. Actually, The solution reduced to find the area under a hyperbola.So, we probably have to use calculus to solve it. There might exist calculus-free method to find the area, because a hyperbola is a special figure in geometry. However, this is a subject of chemistry, and the integration is a general way to find work involved in a thermodynamical process.General chemistry doesn't usually treat this (maybe it's a more advanced concept), and Physical chemistry does.
Oh. Sorry. I thought this was physical chemistry.Yes, that is ln as in natural logarithm.Your units should be J.
Quote from: clinz63 on April 11, 2016, 12:02:54 AMOh. Sorry. I thought this was physical chemistry.Yes, that is ln as in natural logarithm.Your units should be J.How does one get Joules if nothing being plugged in to: w = -nRTln(V2/V1) is in the units of J?