W= -PDeltaV

[David Jen 1J]

When do you use this equation? Is it for only irreversible volume expansions? Are there any limitations to the usage of this equation?

[Chem_Mod]

Use this equation when the volume change is occurring under constant pressure conditions. Since the pressure is constant, it will be irreversible expansion/compression.

[Sondia Luong 1C]

You can use -P∆V when the pressure is constant. Since under constant pressure ∆H = q, your ∆U if you have to solve for internal energy could look like ∆U = ∆H -P∆V

[Audra Mcleod 3G]

Hello!
I would also remind you to keep track of your units when using -PDeltaV, as your units in the final answer will often be L*atm ( pressure will be in atm and volume will be in liters). Thus, you'll usually have to use the conversion 1 L*atm = 101.325 J to get the work in Joules.

[derickngo3d]

This equation is for irreversible expansions only, which occurs at constant pressure.

[Sera Aintablian 2E]

The equation w = -PdeltaV can be used under the following conditions: irreversible, constant external pressure P.

[Jordan Tatang 3L]

for irreversible expansion!

[Edgar Velazquez 2K]

Yes, you can only use it when dealing with an irreversible expansion. So in order to use it, you have to make sure it's irreversible, has a constant pressure, and a non-constant volume.

[Sofia Lombardo 2C]

Yes, this equation can only be used for irreversible expansion. The external pressure must also be constant!

[rhettfarmer-3H]

This would be under the assumption of constant pressure. It is also notes that this equation can be expressed in terms of -dnRT which also gives you the work.

[Kristina Krivenko 3I]

We use this equation when the pressure is kept constant, and there is a volume change.

[Jeremy Wei 2C]

Yes, this equation can only be used for irreversible expansion, where pressure is constant.

[Ziyan Peng 3A]

this equation is only used for irreversible processes and that would also mean that these processes are constant pressure

[Jaden Joodi 3J]

This equation can only be used when work is an irreversible expansion (constant external pressure)

[Megan ODonnell 3F]

Only use it in irreversible conditions when the external pressure is constant!

[IshanModiDis2L]

We use this when we have Irreversibile expansion, or when the volume change is occurring under constant pressure.