Podcast
Questions and Answers
What is any characteristic of a system called?
What is any characteristic of a system called?
A property
Which of the following terms describes those properties of a system which are independent of the system's mass?
Which of the following terms describes those properties of a system which are independent of the system's mass?
Which of the following terms describes properties of a system whose values depend on the size or extent of the system?
Which of the following terms describes properties of a system whose values depend on the size or extent of the system?
Specific volume, specific energy, and density are examples of intensive properties.
Specific volume, specific energy, and density are examples of intensive properties.
Signup and view all the answers
Pressure, temperature, and density are all examples of ______ properties.
Pressure, temperature, and density are all examples of ______ properties.
Signup and view all the answers
Mass, volume, and enthalpy are examples of ______ properties.
Mass, volume, and enthalpy are examples of ______ properties.
Signup and view all the answers
Temperature is an extensive property.
Temperature is an extensive property.
Signup and view all the answers
What is the condition of a system where there is no change in any of its macroscopic properties when isolated from its surroundings?
What is the condition of a system where there is no change in any of its macroscopic properties when isolated from its surroundings?
Signup and view all the answers
Which of the following are NOT a necessary condition for thermodynamic equilibrium?
Which of the following are NOT a necessary condition for thermodynamic equilibrium?
Signup and view all the answers
What is the term for a transformation of a system from one state to another?
What is the term for a transformation of a system from one state to another?
Signup and view all the answers
What term is used to describe the transformation of a system from one equilibrium state to another?
What term is used to describe the transformation of a system from one equilibrium state to another?
Signup and view all the answers
What are the three conditions that must be satisfied for thermodynamic equilibrium?
What are the three conditions that must be satisfied for thermodynamic equilibrium?
Signup and view all the answers
A thermodynamic process always involves a change in temperature.
A thermodynamic process always involves a change in temperature.
Signup and view all the answers
What is the term for the series of states through which a system passes during a process?
What is the term for the series of states through which a system passes during a process?
Signup and view all the answers
The initial and final states of a cycle are identical.
The initial and final states of a cycle are identical.
Signup and view all the answers
What word is derived from the Greek words 'isos' and 'therme', meaning 'equal' and 'heat'?
What word is derived from the Greek words 'isos' and 'therme', meaning 'equal' and 'heat'?
Signup and view all the answers
What is the process where the temperature of the system remains constant?
What is the process where the temperature of the system remains constant?
Signup and view all the answers
In an isothermal process, the change in temperature (dT) is zero.
In an isothermal process, the change in temperature (dT) is zero.
Signup and view all the answers
What is the term for a process involving no exchange of heat between the system and its surroundings?
What is the term for a process involving no exchange of heat between the system and its surroundings?
Signup and view all the answers
An adiabatic process is defined as one in which there is no exchange of heat.
An adiabatic process is defined as one in which there is no exchange of heat.
Signup and view all the answers
The word 'adiabatic' comes from the Greek word 'adiabatos,' meaning 'impassable'.
The word 'adiabatic' comes from the Greek word 'adiabatos,' meaning 'impassable'.
Signup and view all the answers
In an adiabatic process, the change in heat (dq) is zero.
In an adiabatic process, the change in heat (dq) is zero.
Signup and view all the answers
What type of process is defined as one in which the volume remains constant?
What type of process is defined as one in which the volume remains constant?
Signup and view all the answers
In an isochoric process, the initial volume is equal to the final volume.
In an isochoric process, the initial volume is equal to the final volume.
Signup and view all the answers
In an isochoric process, the change in volume (dV) is zero.
In an isochoric process, the change in volume (dV) is zero.
Signup and view all the answers
What type of process is defined as one in which the pressure remains constant?
What type of process is defined as one in which the pressure remains constant?
Signup and view all the answers
In an isobaric process, the initial pressure is equal to the final pressure.
In an isobaric process, the initial pressure is equal to the final pressure.
Signup and view all the answers
In an isobaric process, the change in pressure (dP) is zero.
In an isobaric process, the change in pressure (dP) is zero.
Signup and view all the answers
What is the term for a process that returns the system to its initial state after a series of changes?
What is the term for a process that returns the system to its initial state after a series of changes?
Signup and view all the answers
What is the measure of hotness or coldness of a body?
What is the measure of hotness or coldness of a body?
Signup and view all the answers
What is the law that states that if two bodies are in thermal equilibrium with a third body, then they are in thermal equilibrium with each other?
What is the law that states that if two bodies are in thermal equilibrium with a third body, then they are in thermal equilibrium with each other?
Signup and view all the answers
A thermodynamic property that determines whether or not a system is in thermal equilibrium with another system is called enthalpy.
A thermodynamic property that determines whether or not a system is in thermal equilibrium with another system is called enthalpy.
Signup and view all the answers
What is the term for a process that only passes through equilibrium states?
What is the term for a process that only passes through equilibrium states?
Signup and view all the answers
A quasi-static process is considered a reversible process.
A quasi-static process is considered a reversible process.
Signup and view all the answers
Which of the following are NOT criteria for a reversible process?
Which of the following are NOT criteria for a reversible process?
Signup and view all the answers
What is the term for the process of energy crossing the boundary of a closed system?
What is the term for the process of energy crossing the boundary of a closed system?
Signup and view all the answers
What are the two main forms of energy transfer in a closed system?
What are the two main forms of energy transfer in a closed system?
Signup and view all the answers
Work is usually defined as a force acting through a displacement.
Work is usually defined as a force acting through a displacement.
Signup and view all the answers
What is the sign convention for work done by a system on the surroundings?
What is the sign convention for work done by a system on the surroundings?
Signup and view all the answers
What are the mechanical forms of work transfer?
What are the mechanical forms of work transfer?
Signup and view all the answers
What is the term for work related to a change in volume against pressure?
What is the term for work related to a change in volume against pressure?
Signup and view all the answers
P-dv work is also known as boundary work.
P-dv work is also known as boundary work.
Signup and view all the answers
For an ideal gas, pV = constant is a fixed relationship for isothermal or constant temperature processes.
For an ideal gas, pV = constant is a fixed relationship for isothermal or constant temperature processes.
Signup and view all the answers
What is the term for a process where the pressure and volume are related by pVn = constant, where n is a constant?
What is the term for a process where the pressure and volume are related by pVn = constant, where n is a constant?
Signup and view all the answers
What is the amount of heat required to cause a phase change in unit mass of a substance at constant pressure and temperature?
What is the amount of heat required to cause a phase change in unit mass of a substance at constant pressure and temperature?
Signup and view all the answers
Study Notes
Thermodynamics Properties
- A property is any characteristic of a system.
- Properties can be intensive or extensive.
- Intensive properties do not depend on the mass of the system.
- Extensive properties depend on the size (or extent) of the system.
- Examples of intensive properties: pressure, temperature, density, concentration, melting point, boiling point, surface tension, viscosity.
- Examples of extensive properties: mass, volume, internal energy, heat capacity, enthalpy, entropy, Helmholtz energy, Gibbs energy.
- Specific extensive properties are intensive, such as specific volume, specific energy, and density.
Thermodynamic Equilibrium
- A system is in thermodynamic equilibrium if there is no change in its macroscopic properties when isolated from its surroundings.
- Three conditions must be satisfied:
- Mechanical equilibrium (no unbalanced force).
- Thermal equilibrium.
- Chemical equilibrium (forward and backward reactions are equal).
Process
- A process is a transformation from one state to another.
- The series of equilibrium states a system passes through during a process is called the path.
- When a thermodynamic system changes from one state to another, the operation is a thermodynamic process.
- This involves changes in conditions, like temperature, pressure, and volume.
Types of Thermodynamic Processes
- Isothermal (constant temperature)
- Adiabatic (no heat transfer)
- Isochoric (constant volume)
- Isobaric (constant pressure)
- Cyclic process(initial and final states are identical)
Isothermal Process
- In an isothermal process, the temperature of the system remains constant during the change from initial to final state.
- This process is also known as a "Constant Temperature Process".
- "Isothermal” means “Equal Heat”.
- An example is the boiling of water at constant temperature.
- dT = 0
Adiabatic Process
- In an adiabatic process, there is no exchange of heat between the system and its surroundings during the process.
- Heat transfer is zero; the system is perfectly insulated.
- Energy is transferred only as work.
- dq = 0
Isochoric Process
- In an isochoric process, the volume of the system remains constant during the change from initial to final state.
- The volume change is zero, dV=0.
- An example is boiling water in a closed vessel.
Isobaric Process
- In an isobaric process, the pressure of the system remains constant during the change from initial to final state.
- dp = 0.
- The boiling of water at atmospheric pressure is an example.
Temperature
- Temperature measures the hotness or coldness of a body.
- The zeroth law of thermodynamics states that if body A is in thermal equilibrium with body B, and body B is in thermal equilibrium with body C, then body A is in thermal equilibrium with body C.
Thermometers
- Thermometers are devices used to measure temperature.
- Thermometers use a physical property that changes with temperature to measure temperature.
- Examples: constant volume gas thermometer, constant pressure gas thermometer, electrical resistance thermometer, thermocouple, Mercury-in-glass thermometer.
Quasi-static Process
- A quasi-static process is a process that is nothing but the locus of all the equilibrium states passed through by a system.
- Infinite slowness is the characteristic of a quasi-static process.
- A quasi-static process is a reversible process.
- The process should be quasi static and all the states passed through should be equilibrium states. The conditions should be isothermal, isobaric, and isochoric.
Work Transfer
-
Work is usually defined as a force acting through a displacement.
-
Work done by a system implies its sole effect on surroundings results in the raising of a weight.
-
Work can be transferred between system and surroundings as:
- paddle work
- shaft work
- flow work
- electrical work
- magnetic work.
-
p-V work is performed when the volume changes, which is represented by the area under a P-V diagram.
- p-dV work
Path, Process, and Cycle
- The path of thermodynamic states through which a system passes during a process is called a thermodynamic process.
- Cycle is a sequence of processes in which the initial and final states are identical.
Path Function and Point Function
- Work is a path function, its value depends on the path taken by the system.
- State functions like specific volume, pressure, and temperature are point functions, their values depend only on the current state of the system, not the path it took to get there.
P-V Work on Various Quasi-Static Processes
- Constant pressure (isobaric) process: Work = pΔV
- Constant volume (isochoric) process: Work = 0
Isothermal process (constant temperature)
- Work done by an ideal gas. For an ideal gas, pV = constant, which determines the isothermal process.
- W(1–2) = P1 V1 ln(V2/V1)
Polytropic Process
- For the polytropic process pVn = constant, the work done is calculated as: W(1–2) = (P1V1 – P2V2)/(n–1)
- When n = ∞ (constant volume process) W(1–2) = 0
Adiabatic Work Transfer
- Work transferred during an adiabatic process, where pV^y = constant:
- W(1–2) = (P1V1 − P2V2)/(γ − 1)
Heat Transfer
- Heat is thermal energy in transition between systems due to temperature difference.
- Heat transfer is called "heat" when it crosses the boundary into the or out of the system.
- Positive when heat enters the system, negative when it leaves.
- Adiabatic process: no heat transfer (q=0).
Specific Heat
- Specific heat is the heat required to raise the temperature of one unit of mass by one degree.
- Constant pressure specific heat (Cp) is always greater than constant volume specific heat (Cv), as Cp includes the energy needed to expand against atmospheric pressure during heating.
Latent Heat
- Latent heat is the heat transfer required to cause a phase change at constant pressure and temperature.
- Latent heat of fusion, vaporization, and sublimation.
Sensible Heat
- Sensible heat is the heat exchanged that solely produces a temperature change in a system.
Heat Transfer Mechanisms
- Conduction: Heat transfer through direct contact or temperature difference.
- Convection: Heat transfer between a wall and a fluid in motion (e.g., forced, natural convection).
- Radiation: Heat transfer through electromagnetic waves (e.g., heat transfer from the sun).
Studying That Suits You
Use AI to generate personalized quizzes and flashcards to suit your learning preferences.
Related Documents
Description
Explore the fundamental concepts of thermodynamics, focusing on the distinction between intensive and extensive properties. Additionally, understand the conditions required for a system to reach thermodynamic equilibrium. This quiz will test your knowledge on these essential principles.
