Thermodynamics Laws Quiz

Laws of Thermodynamics

Zeroth Law of Thermodynamics

• If two systems are in thermal equilibrium with a third system, they are also in thermal equilibrium with each other.
• Allows for the definition of a temperature scale, such as the Celsius or Kelvin scale.

First Law of Thermodynamics

• Energy cannot be created or destroyed, only converted from one form to another.
• ΔU = Q - W, where:
  • ΔU is the change in internal energy of a system
  • Q is the heat added to the system
  • W is the work done on the system

Second Law of Thermodynamics

• The total entropy of an isolated system always increases over time, except in reversible processes.
• Entropy (S) measures the disorder or randomness of a system.
• ΔS = ΔQ / T, where:
  • ΔS is the change in entropy
  • ΔQ is the heat added to the system
  • T is the temperature at which the heat is added

Third Law of Thermodynamics

• As the temperature of a system approaches absolute zero, the entropy of the system approaches a minimum value.

Thermodynamic Systems

Types of Systems

• Isolated System: No energy or matter can enter or leave the system.
• Closed System: Energy can enter or leave the system, but matter cannot.
• Open System: Both energy and matter can enter or leave the system.

Thermodynamic Properties

• Internal Energy (U): The total energy of a system, including kinetic energy, potential energy, and potential energy associated with the interactions between particles.
• Enthalpy (H): A measure of the total energy of a system, including internal energy and the energy associated with the pressure and volume of a system.
• Entropy (S): A measure of the disorder or randomness of a system.
• Free Energy (G): A measure of the energy available to do work in a system.

Thermodynamic Processes

Isothermal Process

• A process that occurs at constant temperature.

Adiabatic Process

• A process that occurs without heat transfer between the system and its surroundings.

Isobaric Process

• A process that occurs at constant pressure.

Isochoric Process

• A process that occurs at constant volume.

Laws of Thermodynamics

Zeroth Law of Thermodynamics

• Thermal equilibrium between two systems implies they are also in thermal equilibrium with a third system.
• Enables definition of temperature scales, such as Celsius or Kelvin.

First Law of Thermodynamics

• Energy cannot be created or destroyed, only converted between forms.
• Change in internal energy (ΔU) = heat added (Q) - work done (W) on a system.

Second Law of Thermodynamics

• Total entropy of an isolated system always increases over time, except in reversible processes.
• Entropy (S) measures disorder or randomness of a system.
• Change in entropy (ΔS) = heat added (ΔQ) / temperature (T) at which heat is added.

Third Law of Thermodynamics

• As temperature approaches absolute zero, entropy of a system approaches a minimum value.

Thermodynamic Systems

Types of Systems

• Isolated system: no energy or matter exchange with surroundings.
• Closed system: energy exchange allowed, but matter cannot enter or leave.
• Open system: both energy and matter can enter or leave.

Thermodynamic Properties

• Internal energy (U): total energy of a system, including kinetic, potential, and interaction energies.
• Enthalpy (H): total energy of a system, including internal energy and pressure-volume energy.
• Entropy (S): measure of disorder or randomness of a system.
• Free energy (G): energy available to do work in a system.

Thermodynamic Processes

Isothermal Process

• Occurs at constant temperature.

Adiabatic Process

• Occurs without heat transfer between system and surroundings.

Isobaric Process

• Occurs at constant pressure.

Isochoric Process

• Occurs at constant volume.