## Reversible vs Irreversible

$\Delta S = \frac{q_{rev}}{T}$

joannali1027
Posts: 21
Joined: Fri Sep 25, 2015 3:00 am

### Reversible vs Irreversible

In the book, it says that for the equation Change in Entropy= q/T, they say that heat must be able to be transferred reversibly. It then goes on to say that you can assume that something that is irreversible can be viewed as reversible due to the fact that entropy is a state function. Can someone please explain what that means? I can't make the connection on how it's possible to assume that.

704578485
Posts: 62
Joined: Fri Sep 25, 2015 3:00 am

### Re: Reversible vs Irreversible

A state function is essentially a variable or value that is not dependent on the path it has taken to reach its current value. That means that when discussing entropy changes, we are only concerned with initial and final values and can disregard how those values were achieved since entropy is a state function. With this knowledge, we know our solution is independent of how the entropy value of a system went from point A to point B and can therefore assume irreversible vs. reversible is negligible when discussing entropy.