delta U=0
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Re: delta U=0
Delta U = 0 for isothermal expansions because the temperature is constant in isothermal expansions. When the temperature is constant, no heat could be supplied or released from the process. Thus, delta U = 0. And remember for isothermal (constant temperature) expansions, q=-w, so both q and w would be 0 making delta U 0 as well.
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Re: delta U=0
Hi! In lecture #13, Dr. Lavelle discusses how for isothermal, reversible reactions of ideal gases, any energy lost by the system during expansion (the work value) is replaced in the form of heat absorbed by the system (the q value). Thus, q=-w and by the equation ΔU = q+w , the net change in the internal energy is 0 and because energy that is lost during work is replaced through heat absorbed, the temperature of the system remains the same. Hope this helps!
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Re: delta U=0
Delta U=0 in isothermal reactions because there is no change in temperature. Since U=q+w, in isothermal reactions, q=-w.
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Re: delta U=0
Since the temperature is held constant, the change in energy is zero. The heat absorbed by the gas equals the work done by the ideal gas on its surroundings. Enthalpy change is also equal to zero because the change in energy zero and the pressure and volume is constant. Hope this helps!
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Re: delta U=0
In Isothermal reactions the temperature is constant, so there is no heat transfer. In these reactions q=-w, so they cancel out and leave delta U equal to 0.
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Re: delta U=0
Delta u = 0 because temperature is a constant meaning the change in energy will also be zero. In ideal gas law, enthalpy is a function of temperature, so in isothermal process involving only ideal gases, the change of enthalpy will also be zero.
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Re: delta U=0
Since U=q+w, an isothermal rxn would mean no heat transfer and constant temp, making both values 0.
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Re: delta U=0
This is because the temperature is constant and there is no heat being transferred. Since q=-w they cancel out and the internal energy is zero.
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Re: delta U=0
In an isothermal process, temperature is constant, so the heat absorbed by the gas equals the work done by the ideal gas on its surroundings. Thus, q=-w and by the equation ΔU = q+w , the net change in the internal energy is 0.
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Re: delta U=0
Temperature doesn't change in isothermal processes, so there is no heat or energy being transferred, so delta U is 0.
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Re: delta U=0
delta U is 0 for an isothermal reversible expansion since the amount of energy lost from work is replaced by heat. q= -w
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Re: delta U=0
The change in internal energy (delta U) is 0 for isothermal systems because any heat added to or taken from the system translates directly into work done by (or on) the ideal gas involved. The equation delta U = q+w can be rearranged as q=-w when there is no change in internal energy, indicating that the aforementioned explanation is valid.
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Re: delta U=0
Like many others have stated, Delta U is equal to 0 for isothermal expansions because the temperature stays constant.
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