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In thermodynamics, the macroscopic part of the universe under observation is considered a system.
This system can interact with its surroundings, leading to open, closed, or isolated systems.
Open systems enable the exchange of both matter and energy with their surroundings.
On the other hand, closed systems only allow energy exchange, prohibiting the transfer of matter.
Isolated systems do not permit the exchange of matter or energy.
A system is described quantitatively using state variables, which include pressure, temperature, volume, and the amount of matter.
Each system is separated from its surroundings by a "wall," which can be classified as rigid or nonrigid, permeable or impermeable, and adiabatic or nonadiabatic.
A rigid wall is fixed and does not move, whereas a nonrigid wall can change position like a movable piston.
An impermeable wall does not allow matter to pass through it, while a permeable wall does.
An adiabatic wall does not conduct heat between the system and its surroundings. However, a nonadiabatic wall allows for heat conduction.
Thermodynamics studies the relationship between heat, work, temperature, and energy. A key concept in this field is a "system," the macroscopic part o…
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