## reversible vs irreversible work

Deja Nora
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Joined: Fri Sep 28, 2018 12:22 am

### reversible vs irreversible work

I am a little confused on how you can tell whether a system is reversible or not?

Michael Nguyen 1E
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Joined: Sat Aug 17, 2019 12:17 am

### Re: reversible vs irreversible work

A reversible process is slow and efficient whereas an irreversible process is fast and inefficient. Also, irreversible gas expansions occur under conditions of constant external pressure while reversible gas expansions do not have constant external pressure.

Miriam Villarreal 1J
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Joined: Sat Aug 17, 2019 12:16 am

### Re: reversible vs irreversible work

The work obtained in a reversible is a maximum for the process while the work obtained in a irreversible is not

Posts: 100
Joined: Wed Sep 18, 2019 12:19 am

### Re: reversible vs irreversible work

In a problem, the big difference you need to spot is if the system is pushing against constant pressure or not. If it is it's irreversible but if the pressure changes its reversible.

Maika Ngoie 1B
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Joined: Fri Aug 02, 2019 12:16 am

### Re: reversible vs irreversible work

I think a good tell is whether or not the reaction occurs under constant pressure. That would make it an irreversible reaction.

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Joined: Wed Sep 18, 2019 12:18 am

### Re: reversible vs irreversible work

Oftentimes, the question will also state whether the gas in question "expands reversibly" or "expands irreversibly", so be on the look out for key terms when reading the question!

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### Re: reversible vs irreversible work

Sometimes it's also easy to think conceptually whether a process can be undone (reversible) or not (irreversible) such as combustion, once something is burned then it cannot be undone, therefore it is an irreversible system.

Ying Yan 1F
Posts: 101
Joined: Fri Aug 02, 2019 12:16 am

### Re: reversible vs irreversible work

Usually, there are key works in the problems that tells you if a system is reversible or irreversible. For instance, constant pressure means that the system is irreversible and you would use the equation w=-P(delta)V to calculate work. Hope that helps!

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