Quiz 1 Flashcards
What is the first law of thermodynamics?
Energy is conserved , in any process energy can neither be created or destroyed
What is an open system?
heat and matter exchange with the surroundings
What is a closed system?
only heat exchanges with the surroundings
What is an isolated system?
no heat or matter exchange with the surroundings
What are heat and work (general)
- different means energy is transferred in and out of a system
How does heat transfer energy?
due to temperature changes between system and surroundings
How does work transfer energy?
due to unbalanced forces between system and surroundings
How is the change in internal energy defined?
sum of heat transferred and work done is internal energy
What is a state function?
- depends only on the difference between initial and final STATES, not the path
- internal energy, enthalpy
What is a path function?
- processes that transform one state into another
- work and heat, a system does not contain work or heat but rather these are processes that transform one state into another
What is an intensive quantity?
- doesnt depend on the amount of substance present
- temperature
- pressure
What is an extensive quantity?
- depends on the amount of the substance present
- mass, internal energy
What molecular level properties determine C?
- at constant volume, C depends on internal energy
- U in turn depends on the degrees of freedom a given molecule/substance has (translation, rotation, vibration)
Heat capacity units
(J/K) extensive quantity
Molar heat capacity
(J/K mol) intensive quantity
Specific heat capacity
(J/ K g) heat capacity per mass