Reversible vs Irreversible

[IreneSeo3F]

Can someone explain what reversible and irreversible processes are? What do they tell about the reaction?
For irreversible pathway, do I always use the equation w=-PdeltaV?

[Sam Wentzel 1F 14B]

Reversible has overall entropy increase of 0. Irreversible has entropy increase of positive.

[Kaihan_Danesh_2J]

The irreversible pathway allows for the expansion of gas against a constant external pressure whereas a reversible process requires that the external pressure always match the internal pressure. For example, during a reversible expansion, the pressure external constantly is the same as pressure internal, allowing for maximum work energy to be used. An example of irreversible expansion is a gas expanding against a lower, constant external pressure.

[Katie Phan 1K]

I recommend going back to the lecture where Lavelle distinguished between the two! For an irreversible pathway, work is done against a constant external pressure, and the temperature changes along the pathway. For a reversible pathway, T is constant and V & P are changing.

[Kathy_Li_1H]

Reversible expansions utilize the equation w=-nRTln(V2/V1), have a delta S total equal to zero, and are usually have a greater work value than the irreversible counterpart. Irreversible expansions utilize the w=-P(delta V), involve less work done, and have a delta S surroundings equal to 0. Hope this helps!

[Evonne Hsu 1J]

The reversible pathway refers to when the overall entropy increase is 0, while the irreversible pathway refers to when the overall entropy increase is +.

[Nan_Guan_1L]

I had the same issue understanding the concept. I think for irreversible reactions, the process happens rapidly and the change is significant and relatively larger. But for reversible processes, the changes took multiple steps to happen and each step is not as significant and thus reversible. This is an exaggerated way to explain the concept but I think it helps with making the difference between the two obvious.

[IshanModiDis2L]

The irreversible pathway allows for the expansion of gas against a consistent external pressure but a reversible process means that the external must match the internal pressure as mentioned above.

[Phoebe Joseph]

The irreversible pathway allows for constant external pressure. In order to maintain this constant internal pressure you have to move in infinitesimally small increments so you don't disturb the external pressure. In the reversible pathway you can somewhat ignore the entropy of the surroundings and it can just expand. I think about it like the irreversible pathway is moving in really really small steps to not disturb the outside but the reversible pathways is more bold and doesn't really care about disrupting its surroundings.

[705340227]

Thanks for the clarification!