Register to reply

Entropy Variation - System, Neighborhood and Universe

by jaumzaum
Tags: entropy, neighborhood, universe, variation
Share this thread:
jaumzaum
#1
Mar18-13, 10:59 AM
jaumzaum's Avatar
P: 248
I learned ΔSuniv = ΔSsys + ΔSneib

If ΔSuniv > 0 the process is spontaneous.

But ΔS = Q/T right? Shouldn't Qsys = -Qneib? (The heat released by the system = - heat released by the neighborhood)
I cannot understand why this is wrong!

If it were the case, ΔSuniv would be always zero

Can anyone help me?

[]`s
John
Phys.Org News Partner Chemistry news on Phys.org
Building the ideal rest stop for protons
Direct reaction heavy atoms to catalyst surface demonstrated
Cagey material acts as alcohol factory
DrDu
#2
Mar18-13, 02:01 PM
Sci Advisor
P: 3,564
##\Delta S=Q/T## only for reversible processes.For irreversible processes, ##\Delta S>Q/T##.


Register to reply

Related Discussions
Universe entropy variation of one body and a reservoir Advanced Physics Homework 3
The entropy of the universe? (attempts to define gravitational entropy) Cosmology 22
When will the entropy of universe(an isolated system) stop increasing? Classical Physics 1
How is the entropy of the universe increasing when entropy is simply transferred? Introductory Physics Homework 5
The expanding universe isn't in our neighborhood Astronomy & Astrophysics 3