Delta U


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Ashley Kenney 1E
Posts: 32
Joined: Wed Nov 14, 2018 12:23 am

Delta U

Postby Ashley Kenney 1E » Sun Feb 10, 2019 12:31 am

When is ?

Mona Lee 4L
Posts: 60
Joined: Fri Sep 28, 2018 12:16 am

Re: Delta U

Postby Mona Lee 4L » Sun Feb 10, 2019 1:06 am

DeltaU = q + W. Therefore, the internal energy of a system does not change only when q and W are zero.

maldonadojs
Posts: 57
Joined: Fri Sep 28, 2018 12:27 am

Re: Delta U

Postby maldonadojs » Sun Feb 10, 2019 1:40 am

Delta U is 0 when you are dealing w a isothermal/reversible reaction.

Tuong Nguyen 2I
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Joined: Fri Sep 28, 2018 12:26 am
Been upvoted: 1 time

Re: Delta U

Postby Tuong Nguyen 2I » Sun Feb 10, 2019 2:20 am

Well delta U can still have a nonzero value at isothermal, reversible processes depending on what w is. So when we know that the system undergoes an isothermal, reversible process, we know that heat (q) = 0 and therefore the only thing left for delta U to equal is w.

So at isothermal, reversible processes, delta U = work (w).

Kavvya Gupta 1H
Posts: 35
Joined: Fri Sep 28, 2018 12:21 am

Re: Delta U

Postby Kavvya Gupta 1H » Sun Feb 10, 2019 9:38 am

delta u is zero when there is no temperature change

Nicole Elhosni 2I
Posts: 62
Joined: Fri Sep 28, 2018 12:28 am

Re: Delta U

Postby Nicole Elhosni 2I » Sun Feb 10, 2019 9:56 am

Since for an ideal gas the internal energy is proportional to temperature, it follows that there is no change in the internal energy of the gas during an isothermal process.

Maya_Peterson1C
Posts: 62
Joined: Fri Sep 28, 2018 12:28 am

Re: Delta U

Postby Maya_Peterson1C » Sun Feb 10, 2019 12:50 pm

The internal energy is zero when it is a reversible reaction or if it is at a constant temperature.

Niveda_B_3I
Posts: 60
Joined: Fri Sep 28, 2018 12:24 am

Re: Delta U

Postby Niveda_B_3I » Sun Feb 10, 2019 4:54 pm

The change in internal energy could be 0
if q = -w
if T = 0
and if the system is isothermal and the reaction is reversible

Jacob Bershatski 4C
Posts: 30
Joined: Fri Sep 28, 2018 12:21 am

Re: Delta U

Postby Jacob Bershatski 4C » Sun Feb 10, 2019 8:17 pm

Based on the equation, deltaU=(3/2)nR(deltaT), deltaU is 0 when deltaT is 0. I am still a little confused about this myself. However, whenever you have an isolated system, deltaU always equals 0 because heat and work cannot be transferred into or out of the system.


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