Reversible and Irreversible Expansion

[Jada Brown 2H]

What are reversible and irreversible expansion? What do they mean?

[Brian_Ho_2B]

Reversible expansions allow the gas to return to its original volume naturally on its own. Irreversible expansions change to a certain volume and stay there. There are different equations for the work done by expansion for each of those cases. For reversible expansions, w = -nRT*ln(V2/V1) and for irreversible expansions against an external pressure, w = -P(exterior)* change in Volume.

[Harry Zhang 1B]

Reversible expansion means when the expansion can be reversed by an infinitesimal change, while irreversible means when an infinitesimal change will not reverse the direction of expansion.