Physics #3 Flashcards
the zeroth law of thermodynamics
2 objects in thermal equilibrium will not participate in heat exchange.
Also, if a=b and b=c then a=c.
at the molecular level, temperature if proportional to the _______
average kinetic energy of the particles that make up the substance.
thermal equilibrium occurs when ____ heat is transferred between two objects in thermal contact
no
the third law of thermodynamics
the entropy of a perfectly organized crystal at absolute zero is 0.
how does a material’s linear expansion coefficient compare to its volumetric expansion coefficient?
Beta = 3xalpha
is there a maximum distance at which thermal contact does not exist?
no, thermal contact will always exist no matter how far apart two objects are. It might just be very very miniscule at large distances.
compare the length change of 2 objects that differ starting lengths but increase temperature the same
the object that was longer to start will undergo a greater change in length (formula)
accuracy is related to an ____, not a scale
instrument
isolated system
cannot exchange energy or matter with the surroundings
in an isolated system, internal energy change = ___
0
____ are thermodynamic properties that are a function of only the current equilibrium state of a system, while ____ describe the path taken to get from one state to another
state functions
process functions
list the state functions
pressure, volume, density, temperature, enthalpy, internal energy, gibbs free energy, entropy
list the process functions
heat and work
first law of thermodynamics
internal energy conserved
mechanical energy conserved when no nonconservative forces present
what can lead to an increase in the internal energy of a system
increase in heat or work done on the system.
second law of thermodynamics
objects in thermal contact and not in thermal equilibrium will exchange heat energy such that the object with the higher temperature will give off heat energy to the object with a lower temperature until both objects have the same temperature at thermal equilibrium
energy is spontaneously dispersed from being localized to becoming spread out of it is not hindered from doing so.
the energy of the universe is increasing
what is heat?
the process by which a quantity of energy is transferred between two objects as a result of a difference in temperature.
describe conduction
need direct physical contact: kinetic energy is transferred from particles of the hotter matter to particles of the cooler matter
describe convection
the transfer of heat by the physical motion of a fluid over a material
describe radiation
transfer of energy by electromagnetic waves
only ____ and _____ can transfer heat by convection
liquids and gases
which type of heat transfer does not need matter to transfer heat?
radiation
define the specific heat of a substance
defined as the amount of heat energy required to raise 1 g of a substance by one degree Celsius.
will the temperature of a substance start to increase before all of the solid is changed to liquid?
no, all solid must be changed to liquid before the substance will begin to rise in temperature.
phase changes are related to changes in ______ not kinetic energy
potential energy
liquid water and ice have the _______ kinetic energy at the same temperature
same
solid to liquid
melting/fusion
liquid to gas
vaporization/evaporation/boiling
what is another word for melting
fusion
gas to liquid
condensation
liquid to solud
freezing or solidification
solid to gas
sublimation
gas to solid
deposition
what is the name of the heat of transformation for solid to liquid/liquid to solid
heat of fusion
what is the name of the heat of transformation for liquid to gas or gas to liquid
heat of vaporization
the heat of fusion represents how much heat is require to _____
completely melt a substance of some mass.
for a closed loop process, how do you calculate the work done
work is a process function so it is path dependent so you can look at each step.
overall, you will simply take the area within the curve of a pressure-volume graph.
entropy
the spontaneous dispersal of energy at a specific temperature
what are the units for entropy
J/(mol)(K)
calorimeters are attempts at ____ systems
isolated
1 degree celsius is equal to _____ degrees Farenheit
1.8
1 degree celsius is equal to _____ degrees Farenheit
1.8
when calculating the work from a pressure volume graph loop, a loop in the clockwise direction does _____ work on the environment
positive
_____ are our best approximations of isolated systems
calorimeters
convection requires ____ of a fluid
flow
According to the second law of thermodynamics, the overall entropy change of a system ______ in a thermodynamic process that moves from one equilibrium state to another
can never be negative
