delta S reversible and irreversible

[Susie 2D]

What is the difference in solving for delta s for reversible and irreversible reactions.

[905994971]

For irreversible vs. reversible reactions it's important to consider the delta S for the system versus the surroundings.

For reversible reactions delta S (system) = - delta S (surroundings) because delta S (system) + delta S (surroundings) = delta S (universe) and delta S (universe) for reversible reactions is always 0.

For irreversible reactions delta S (surroundings) = 0 because the system is contained.

[vkhauv2004]

With reversible delta S, since delta S goes both ways, the overall delta S universally should equal to 0. Thus delta S of your system would equal - delta S of your surroundings. With irreversible delta S, there is 0 work put into the surroundings of delta S. Therefore, delta S of your surroundings would equal 0.

[Maegan Abutin 2C]

Hi!

The main difference for solving entropy changes for reversible and irreversible reactions is the formulas. For reversible reactions, entropy change can be solved using the formula: W=nRT*ln(Vf-VI). On the other hand, entropy change can be solved using a simpler formula: W=-P(ext)△V.

Hope this helps!

[Averie Moore 2F]

In reversible reactions delta S uses infinitesimally small changes in heat with respect to temperature over the entire process. In irreversible reactions, entropy changes can sometimes be estimated but may not follow a straightforward process. The nature of the processes and the methods used to calculate entropy changes differentiate calculating delta S in reversible and irreversible reactions.