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Ch 19: Work, Heat, and the First Law of Thermodynamics
Chapter 19, Problem 19

n moles of an ideal gas at temperature T1 and volume V1 expand isothermally until the volume has doubled. In terms of n, T₁ , and V₁, what are (b) the work done on the gas, and

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Key Concepts

Here are the essential concepts you must grasp in order to answer the question correctly.

Isothermal Process

An isothermal process is a thermodynamic process in which the temperature of the system remains constant. For an ideal gas, this means that any heat added to the system is used to do work, rather than increasing the internal energy. In the context of the question, the gas expands isothermally, which allows us to apply the ideal gas law and the principles of thermodynamics to calculate work done.
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Work Done by an Ideal Gas

The work done by an ideal gas during expansion or compression can be calculated using the formula W = ∫ P dV, where P is the pressure and dV is the change in volume. For isothermal expansion, this can be simplified using the ideal gas law (PV = nRT) to find that W = nRT ln(Vf/Vi), where Vf and Vi are the final and initial volumes, respectively. This relationship is crucial for determining the work done on the gas in the given scenario.
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Ideal Gas Law

The ideal gas law is a fundamental equation in thermodynamics that relates the pressure, volume, temperature, and number of moles of an ideal gas. It is expressed as PV = nRT, where P is pressure, V is volume, n is the number of moles, R is the ideal gas constant, and T is temperature. This law is essential for understanding the behavior of gases and is particularly useful in calculating the work done during isothermal processes.
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