Unit 2 - Thermodynamics Flashcards
Energy
capacity to do work
Kinetic Energy
due to motion
Thermal Energy
associated with temperature
Potential Energy
- due to position or composition
- energy available by virtue of an object’s position
Chemical Energy
Associated with Positions of Electrons and Nuclei
Radiant Energy
comes from the sun and is earth’s primary earth source
Nuclear energy
energy stored within the collection of neutrons and protons in the atom
Law of Conservation of Energy
- energy cannot be created nor destroyed
- total amount of energy in the universe is constant
Thermochemistry
study of heat change in chemical reactions
System
specific part of the universe that is of interest in the study.
Joule (unit of energy)
1 J = 1 kg times m^2/s^2
Kinetic Energy
KE = 1/2mv^2
Conservation of Energy
Change in Energy universe = 0 = Change in Energy system + Change in Energy surroundings
State Function
- properties that are determined by the state of the system, regardless of how that condition was achieved.
Energy Diagrams
- graphically shows the direction of energy flow
- if energy enters the system, it will be positive (+)
- if energy leaves the system, it will be negative (-)
First Law of thermodynamics
- energy can be converted from one form to another, but cannot be created or destroyed
change in energy system = - change in energy surroundings
Energy Exchange (formula)
change in energy = q+w
q= heat (thermal) energy
w = work energy
Heat
- exchange of thermal energy
Specific Heat (Cs)
amount of heat required to raise the temperature of one gram of the substance by one degree Celsius
q=mCs (change in temperature)
Heat Capacity (C)
- amount of heat required to raise the temperature of a given quantity (m) of the substance by one degree Celsius
q = C change in temperature
Heat Transfer
- heat flows from the material at the higher temperature to the material at the lower temperature
- flows until both materials reach the same final temperature
- amount of heat energy lost by the hot material equals the amount of heat gained by the cold material
