So our secret (or not so secret rather) instructions say that we need to write out a bunch of definitions for 20% of our midterm, and no examples can be given otherwise marks will be docked.
I'm going to include key terms from each of the lectures here. This list is most likely incomplete, but I'm going to post what I have so far and add to it later. :) The main sources for these definitions were the lecture notes and the hardcopy of the textbook. And of course, wikipedia. cough, cough.
Lecture 1
system: that part of the universe of interest
open system: a system where matter or energy can flow into/out of the system
closed system: a system where energy can flow into/out of the system, but matter cannot
isolated system: neither matter nor energy can enter/exit the system, only move around inside
temperature: physical property related to the measure of the average kinetic energy of the atoms or molecules of a substance; degree of hotness of a body, substance, medium
thermal equilibrium: any flow of heat into or out of a body is equal to the flow of heat into or out of another body, the two bodies have the same temperature (also applies to more than two bodies)
exothermic: energy is released from the system, weaker bonds go to stronger bonds
endothermic: energy is absorbed by the system, stronger bonds go to weaker bonds
Zeroth Law of Thermodynamics: If system A is in equilibrium with system B and system B is in equilibrium with system C, then system A is in equilibrium with system C and A, B, and C have the same temperature.
state: defined by the parameters that are measured and describe a system under these conditions
Lecture 2 and 3
thermal energy: (this is really difficult to define, so the definition I provide is half-a**ed aka ambiguous from the prof's notes) the energy around us, part of the total internal energy of a thermodynamic system or sample of matter, partly the kinetic energy of the system's particles, equally partitioned between all degrees of freedom of particles (translational, vibrational, rotational), not a state function or property of a system as depends on path taken
*potential energy diagram*
I will discuss the BE diagram of a diatomic molecule in another post, as this shows up time after time and it might be important for the course. :) Yay!
cold temperatures: temperatures less than 1000-2000 K, restricts chemistry
internal energy: energy needed to create system from atoms, contains kinetic energy of motion (moving, rotating, vibrating), as well as electrostatic energy of the attraction and repulsion of electrons and nuclei [excludes PV work on the surroundings]
heat: transfer of energy from high to low temperature by conduction, radiation, convection; path dependent
work: energy transferred by a force acting on a distance; path dependent
PV work:
state function: property of a system whose value does not depend on the path taken to reach that specific value, only dependent on initial and final conditions
reversible path: maintains equilibrium between the system and surroundings throughout the change from the initial state to the final state; most efficient path
non-reversible path: does not maintain equilibrium between the system and surroundings throughout the change from the initial state to the final state, cannot not be undone, inefficient
The First Law of Thermodynamics: U=q+w
Thermodynamics: gives relationships between states at equilibrium
Lecture 4
heat capacity: the amount of heat required to raise the temperature of any substance by 1 K; includes the ability for a substance to store energy the various degrees of freedom in movement/translation, rotation, and vibration of the particles
Enthalpy: H= U + PV
isochoric process: process occurring at constant volume (the internal energy is equal to the heat of the system)
isobaric process: process occurring at constant pressure (the enthalpy is equal to the heat of the system)
isothermal process: process occurring at constant temperature
Lecture 5
No vocab, just a proof dealio about state functions and Euler's criterion for exactness, which will not show up on the exam as involves material beyond the scope of the course.
Lecture 6
thermochemistry: study of the heats of reactions under various conditions
*bond energy diagram shows up again*
Lecture 7
equipartition of energy: in thermal equilibrium, the energy is shared equally among all of its various forms, such as translational, rotational, and vibrational components of a molecule
^
(stay tuned for an upcoming post about this long topic)
Lecture 8
bond energy: energy needed to break a bond, always positive as energy put into the system
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