## Irreversible and reversible heat transfer

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

npinak_2D
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### Irreversible and reversible heat transfer

What is importance of irreversible and reversible heat transfers? What are the major differences between the two processes?

Chem_Mod
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### Re: Irreversible and reversible heat transfer

Hi,

In a reversible process, the system can be made to go back to it's initial state by infinitesimal changes in some property of system without the expenditure of energy.

In a Irreversible process you need to spend some energy to take the system back to it's initial state.

704628249
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### Re: Irreversible and reversible heat transfer

Usually irreversible processes occur under constant pressure and irreversible processes do not. Irreversible processes do more work.

Chem_Mod
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### Re: Irreversible and reversible heat transfer

It should be the other way around. Reversible process actually does more work (maximum work). Plus, in isothermal expansion, the irreversible one pushes against a constant pressure while the reversible one does not.