Thermodynamics Flashcards
Define a Thermodynamic System
The particular thing or part of the physical universe that we choose to study
Define Boundary
The real or imaginary separation between the system and the rest of the universe. If clearly defined the system can exchange energy and matter.
Define Surroundings
The part of the universe that is outside the system (everything else)
Define Universe
The system and surroundings
Define Open System
Can exchange both energy and matter with the surroundings (both energy and matter can cross the boundary)
Define a closed system
Can exchange energy, but not matter, with the surroundings
Define an isolated system
Cannot exchange energy or matter with the surroundings
Define State variables (aka state variables)
Describes the conditions of a system. Does not depend on how that state was achieved (path independent).
Give some examples of state variables
Examples: temperature, pressure, volume, density, mass, and concentration.
Define Intensive Variables
Independent of the size of the system (size does not matter)
Define extensive variable
Dependant on size of the system (changes with size and only size, not volume)
What are some examples of intensive variables?
Pressure, temperature, density, number of moles, molar mass, and concentration.
What are some examples of extensive variables?
Volume, mass, and energy.
How do you change extensive to intensive and vise versa?
Ext / Int = Ext
Ext / Ext = Int
You cannot change an intensive variable to extensive.
How do you change extensive to intensive and vise versa?
Ext / Int = Ext
Ext / Ext = Int
You cannot change an intensive variable to extensive.
