## Expansion against constant pressure

$w=-P\Delta V$
and
$w=-\int_{V_{1}}^{V_{2}}PdV=-nRTln\frac{V_{2}}{V_{1}}$

Kayla T 1J
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### Expansion against constant pressure

Is expansion against constant pressure in a system reversible? Would it be considered reversible in the case of an infinite number of steps?

katielee1K
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Joined: Mon Jan 26, 2015 2:17 pm

### Re: Expansion against constant pressure

when a reaction is has constant pressure it is irreversible. For an irreversible expansion, there is an inequality between the external and internal pressures of the system, and thus one form of volume change (either expansion or contraction) occurs.

Chem_Mod
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### Re: Expansion against constant pressure

Constant pressure can occur in a reversible process (isobaric process). In that case they heat up the system. As long as it occur in a gradual manner, it would be defined as reversible process. If you heat up the system so fast that the pressure of the system shoots up, then it is irreversible.