internal energy ideal gas

isochoric/isometric:
isothermal:
isobaric:

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905290504
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internal energy ideal gas

Postby 905290504 » Fri Feb 12, 2021 8:20 am

why is the ∆U = 0 for an isothermal expansion of an ideal gas?

Edison Tham 3D
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Re: internal energy ideal gas

Postby Edison Tham 3D » Fri Feb 12, 2021 11:54 am

For an isothermal expansion of an ideal gas, the amount of work that the system does is replaced by the same amount of heat (which is how the system is isothermal). Since we know that ∆U=q+w, the work done to the system is going to be negative (for expansion) and the heat would be put into the system (the same value but positive), so overall ∆U would equal 0.

Alexandra Salata 2L
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Re: internal energy ideal gas

Postby Alexandra Salata 2L » Fri Feb 12, 2021 2:44 pm

In Isothermal process the temperature is constant. The internal energy is a state function dependent on temperature. Therefore, the internal energy change is 0.

Chinmayi Mutyala 3H
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Re: internal energy ideal gas

Postby Chinmayi Mutyala 3H » Sun Feb 14, 2021 11:51 am

The work done is replaced by heat so Q = -W. Since delta U = Q + W, it would be 0.

Andrew Yoon 3L
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Re: internal energy ideal gas

Postby Andrew Yoon 3L » Sun Feb 14, 2021 8:07 pm

∆U = 0 for an isothermal expansion of an ideal gas because the work that is done within the system is replaced by energy in the form of heat. This means that Q = -W, which also can be written as ∆U = Q + W, which also equals 0.

Susanna Givan 2B
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Re: internal energy ideal gas

Postby Susanna Givan 2B » Sun Mar 14, 2021 10:20 pm

Are there other instances in which Delta U is 0?


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