wiz-icon
MyQuestionIcon
MyQuestionIcon
1
You visited us 1 times! Enjoying our articles? Unlock Full Access!
Question

For a sample of perfect gas when its pressure is changed isothermally from pi to pf, the entropy change is given by:

A
ΔS = nR ln(pfpi)
No worries! We‘ve got your back. Try BYJU‘S free classes today!
B
ΔS = nR ln(pipf)
Right on! Give the BNAT exam to get a 100% scholarship for BYJUS courses
C
ΔS = nRT ln(pfpi)
No worries! We‘ve got your back. Try BYJU‘S free classes today!
D
ΔS = RT ln(pipf)
No worries! We‘ve got your back. Try BYJU‘S free classes today!
Open in App
Solution

The correct option is A ΔS = nR ln(pipf)
Solution:- (B) ΔS=nRln(PiPf)
For measurable change between two states, i.e., initial (i) and final (f)-
ΔS=fidqT
As the temperature is constant,
ΔS=1Tfidqrev.
As we know that,
dqrev.=dwrev.=nRT(dVV)
ΔS=1TfinRT(dVV)
ΔS=nRTTfi(dVV)
ΔS=nRlnVfVi
From Charle's law,
PfVf=PiVi
VfVi=PiPf
ΔS=nRln(PiPf)

flag
Suggest Corrections
thumbs-up
0
Join BYJU'S Learning Program
similar_icon
Related Videos
thumbnail
lock
Spontaneity and Entropy
CHEMISTRY
Watch in App
Join BYJU'S Learning Program
CrossIcon