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What is the work done when 18.0 g of liquid water is vaporized at 100°C against a constant external pressure of 1.00 atm?
What is the work done when 18.0 g of liquid water is vaporized at 100°C against a constant external pressure of 1.00 atm?
What is the change in internal energy (ΔE) for the system that absorbs 140 J of heat and does 85 J of work on the surroundings?
What is the change in internal energy (ΔE) for the system that absorbs 140 J of heat and does 85 J of work on the surroundings?
If a system loses 79 kJ of heat and performs 213 kJ of work on its surroundings, what is the value of ΔE?
If a system loses 79 kJ of heat and performs 213 kJ of work on its surroundings, what is the value of ΔE?
Given the ideal gas constant R = 0.0820 L atm K⁻¹ mol⁻¹, what is the value of work calculated in calories when the volume change during vaporization is 30.582 L.atm?
Given the ideal gas constant R = 0.0820 L atm K⁻¹ mol⁻¹, what is the value of work calculated in calories when the volume change during vaporization is 30.582 L.atm?
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What is the ideal gas equation for vapor in terms of temperature and constant, if PV = nRT is applied?
What is the ideal gas equation for vapor in terms of temperature and constant, if PV = nRT is applied?
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What occurs during isothermal reversible expansion of an ideal gas?
What occurs during isothermal reversible expansion of an ideal gas?
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Which equation describes the slope of the isothermal reversible expansion process?
Which equation describes the slope of the isothermal reversible expansion process?
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What is the primary difference between isothermal and adiabatic processes in terms of heat exchange?
What is the primary difference between isothermal and adiabatic processes in terms of heat exchange?
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For an adiabatic reversible expansion, which relationship holds true?
For an adiabatic reversible expansion, which relationship holds true?
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What is the heat absorbed (q) during the conversion of one mole of benzene into vapor, given the heat of vaporization and molecular weight?
What is the heat absorbed (q) during the conversion of one mole of benzene into vapor, given the heat of vaporization and molecular weight?
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Which graph correctly represents the pressure versus volume relationship for isothermal and adiabatic processes?
Which graph correctly represents the pressure versus volume relationship for isothermal and adiabatic processes?
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In an isothermal irreversible process, what is true about work done (w) compared to a reversible process?
In an isothermal irreversible process, what is true about work done (w) compared to a reversible process?
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What characterizes the adiabatic reversible expansion in terms of energy transfer?
What characterizes the adiabatic reversible expansion in terms of energy transfer?
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What is the final temperature in Kelvin after the air has expanded adiabatically from an initial temperature of $298K$?
What is the final temperature in Kelvin after the air has expanded adiabatically from an initial temperature of $298K$?
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In an adiabatic process, when the quantity of air expands, what remains constant?
In an adiabatic process, when the quantity of air expands, what remains constant?
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How is the work of adiabatic compression calculated?
How is the work of adiabatic compression calculated?
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If the initial temperature of the gas is $25°C$, what is it in Kelvin?
If the initial temperature of the gas is $25°C$, what is it in Kelvin?
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What equation would be used to calculate the change in enthalpy, $ riangle H$, for an ideal gas?
What equation would be used to calculate the change in enthalpy, $ riangle H$, for an ideal gas?
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What is the effective value of Cv if Cv for the process is 5 cal deg$^{-1}$ mole$^{-1}$?
What is the effective value of Cv if Cv for the process is 5 cal deg$^{-1}$ mole$^{-1}$?
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Which of the following equations represents energy change in an adiabatic process?
Which of the following equations represents energy change in an adiabatic process?
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How is the final temperature $T2$ related to the initial temperature $T1$ in a given pressure change?
How is the final temperature $T2$ related to the initial temperature $T1$ in a given pressure change?
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For an ideal gas undergoing adiabatic processes, the relationship between specific heats is given by which of the following equations?
For an ideal gas undergoing adiabatic processes, the relationship between specific heats is given by which of the following equations?
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What is the relationship between heat capacity at constant pressure and constant volume for an ideal gas?
What is the relationship between heat capacity at constant pressure and constant volume for an ideal gas?
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In an isothermal reversible process, what is the change in internal energy (ΔE)?
In an isothermal reversible process, what is the change in internal energy (ΔE)?
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If an ideal gas undergoes adiabatic expansion, what happens to the temperature?
If an ideal gas undergoes adiabatic expansion, what happens to the temperature?
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What is the equation that describes the work done (w) during an adiabatic process for an ideal gas?
What is the equation that describes the work done (w) during an adiabatic process for an ideal gas?
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For an ideal gas, the relation between temperature and volume in a reversible adiabatic process can be described by which of the following?
For an ideal gas, the relation between temperature and volume in a reversible adiabatic process can be described by which of the following?
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In which type of process does the change in internal energy equal the work done on the system?
In which type of process does the change in internal energy equal the work done on the system?
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What does the term 'Joule experiment' refer to in the context of thermodynamics?
What does the term 'Joule experiment' refer to in the context of thermodynamics?
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Which equation represents the relationship between heat transfer (dq), work done (dw), and internal energy change (dE)?
Which equation represents the relationship between heat transfer (dq), work done (dw), and internal energy change (dE)?
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For which scenario is the change in enthalpy (ΔH) equal to zero?
For which scenario is the change in enthalpy (ΔH) equal to zero?
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In an irreversible isothermal process, what is the expression for work done (w)?
In an irreversible isothermal process, what is the expression for work done (w)?
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What is the effect of temperature on pressure during a reversible adiabatic process?
What is the effect of temperature on pressure during a reversible adiabatic process?
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What does the value of γ (gamma) signify in thermodynamics?
What does the value of γ (gamma) signify in thermodynamics?
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During adiabatic compression, what happens to the internal energy of a system?
During adiabatic compression, what happens to the internal energy of a system?
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Which expression represents the condition for an ideal gas during an adiabatic process?
Which expression represents the condition for an ideal gas during an adiabatic process?
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Study Notes
First Law of Thermodynamics
- The first law of thermodynamics states that the change in internal energy of a system is equal to the heat added to the system minus the work done by the system.
- This is represented by the equation: ΔE = q - w
- The internal energy of a system is a function of temperature, pressure, and volume.
- The heat capacity at constant volume (Cv) is the change in internal energy per degree change in temperature at constant volume.
- The heat capacity at constant pressure (Cp) is the change in enthalpy per degree change in temperature at constant pressure.
- For an ideal gas, Cp - Cv = R, where R is the ideal gas constant.
Isothermal Reversible Process
- For an isothermal reversible process, the temperature remains constant, therefore the change in internal energy is zero (ΔE = 0).
- The work done by the system is equal to the heat absorbed by the system (w = q).
- The work done in an isothermal reversible process can be calculated using the following equation: w = nRTln(V2/V1), where n is the number of moles of gas, R is the ideal gas constant, T is the temperature, V1 is the initial volume, and V2 is the final volume
Adiabatic Reversible Process
- For an adiabatic reversible process, there is no heat exchange between the system and the surroundings (q = 0).
- The change in internal energy is equal to the negative of the work done by the system (ΔE = -w).
- For an ideal gas undergoing an adiabatic reversible process, the following relationship between temperature and volume holds: T2/T1 = (V1/V2)^(γ-1), where γ is the adiabatic index (γ = Cp/Cv).
Adiabatic Irreversible Process
- In an adiabatic irreversible process, the pressure is constant, and the work of expansion is given by: w = P2(V2 - V1)
- The energy change in an adiabatic irreversible process is ΔE = -w = -P2(V2 - V1).
- The relationship between temperature and volume for an adiabatic irreversible process can also be derived using the first law of thermodynamics.
Enthalpy
- Enthalpy is a thermodynamic property that is defined as the sum of the internal energy of a system and the product of its pressure and volume.
- It is a measure of the total energy of a system, including both internal energy and potential energy due to pressure and volume.
- The change in enthalpy (ΔH) of a system is equal to the heat absorbed by the system at constant pressure.
- For an ideal gas, ΔH = nCp(T2 - T1).
Comparing Isothermal and Adiabatic Processes
- A plot of pressure vs volume for both isothermal and adiabatic reversible expansions with the same initial point will show two curves, one for each process.
- The isothermal curve will have a lower negative slope (less steep) while the adiabatic curve will have a higher negative slope (steeper). This is because in an adiabatic process, the temperature of the system is not constant and it changes as the system expands, causing a greater change in pressure.
- The area under the P-V curve will be greater for the isothermal reversible expansion than the adiabatic reversible expansion.
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Description
Test your understanding of the first law of thermodynamics and isothermal reversible processes. This quiz covers key concepts such as internal energy, heat capacity, and the relationships between heat, work, and internal energy changes in a system. Challenge yourself and see how well you grasp these foundational principles of thermodynamics.
