An irreversible isothermic expansion?

[Mr Skeptic]

Is there such a thing as an isothermic irreversible expansion of a gas against a constant external pressure? Could some one give me a physical example of one?

[J.C.MacSwell]

Is there such a thing as an isothermic irreversible expansion of a gas against a constant external pressure? Could some one give me a physical example of one?

 

It can be done, at least approximately, slowly and carefully, at least if you accept a change of state as expansion.

 

That it's "irreversible" is a given for any heat transfer.

 

What are you trying to accomplish?

Edited October 27, 2009 by J.C.MacSwell

[Mr Skeptic]

No, I mean theoretically irreversible, as in thermodynamics theory. It would only be irreversible if there was a change in temperature as well as heat transfer, I would think. Anyhow, I got a homework problem to calculate some things about such a system, but I don't think that such a system can exist.