reversible vs irreversible work

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Deja Nora
Posts: 11
Joined: Fri Sep 28, 2018 12:22 am

reversible vs irreversible work

Postby Deja Nora » Thu Feb 06, 2020 8:07 pm

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

Michael Nguyen 1E
Posts: 120
Joined: Sat Aug 17, 2019 12:17 am

Re: reversible vs irreversible work

Postby Michael Nguyen 1E » Thu Feb 06, 2020 8:23 pm

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
Posts: 105
Joined: Sat Aug 17, 2019 12:16 am

Re: reversible vs irreversible work

Postby Miriam Villarreal 1J » Fri Feb 07, 2020 7:48 am

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

Cooper Baddley 1F
Posts: 100
Joined: Wed Sep 18, 2019 12:19 am

Re: reversible vs irreversible work

Postby Cooper Baddley 1F » Fri Feb 07, 2020 9:05 am

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
Posts: 97
Joined: Fri Aug 02, 2019 12:16 am

Re: reversible vs irreversible work

Postby Maika Ngoie 1B » Sat Feb 08, 2020 12:46 pm

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

CMaduno_1L
Posts: 102
Joined: Wed Sep 18, 2019 12:18 am

Re: reversible vs irreversible work

Postby CMaduno_1L » Sun Feb 09, 2020 1:20 am

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!

Kayla Maldonado 1C
Posts: 107
Joined: Sat Aug 17, 2019 12:16 am
Been upvoted: 1 time

Re: reversible vs irreversible work

Postby Kayla Maldonado 1C » Sun Feb 09, 2020 1:45 am

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

Postby Ying Yan 1F » Sun Feb 09, 2020 12:42 pm

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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