Isothermal reversible of ideal gas


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Isothermal reversible of ideal gas

Postby aphung1E » Thu Feb 13, 2020 8:59 am

Can someone tell me what values such as heat, pressure, etc are equals to zero in an ideal gas of an isothermal reversible system?

Ashley Tran 2I
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Re: Isothermal reversible of ideal gas

Postby Ashley Tran 2I » Thu Feb 13, 2020 10:38 am

Isothermal reversible just means the temp stayed constant so q=-w and you can use the equation nrlnv2/v1 to calculate entropy of the system.

Ally Huang- 1F
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Re: Isothermal reversible of ideal gas

Postby Ally Huang- 1F » Thu Feb 13, 2020 11:33 am

Delta U is equal to zero for an isothermal reversible system. The same amount of heat enters the system as the work that leaves the system so the temperature stays constant and delta U will also equal zero based on DeltaU=q+w.

Pegah Nasseri 1K
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Re: Isothermal reversible of ideal gas

Postby Pegah Nasseri 1K » Thu Feb 13, 2020 10:22 pm

An ideal gas in an isothermal, reversible reaction will have an internal energy of 0. This means that the heat will equal the negative energy of the work done:

Delta U = q + w = 0
This indicates that: q = -w

In addition, the total change in entropy will be zero:
This indicates that:

Use the equation to find the change in entropy of the system.
Because the initial and final states of the system are the same since the reaction is returning to its initial state, both the internal energy and total change in entropy is zero.

Helen Struble 2F
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Re: Isothermal reversible of ideal gas

Postby Helen Struble 2F » Sun Feb 16, 2020 5:56 pm

Delta U will equal 0, because q = -w. This simply means that any energy transferred from system to surroundings as work will immediately be replaced by a flow of heat from surroundings to system (or vice versa, depending on if it's an expansion or compression). Because there is no net change in energy, there is no temperature change, making it isothermal. Pressure and volume both change variably depending on the problem.

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