PORTAGE CHEM 104 – MODULE EXAM. MODULE 1-7 EXAM
STUDY GUIDE. // GRADED A+ // NEWEST EXAM STUDY
GUIDE // 2025 UPDATE
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MODULE 1
heat (q) - ANS✔✔-the transfer of thermal energy between two bodies at diff
temps
work (w) - ANS✔✔-transfer of mechanical energy causing matter to move
against an opposing force
potential energy - ANS✔✔-energy an object has because of its relative position
kinetic energy - ANS✔✔-the energy that an object possesses because of its
motion
1st law of thermodynamics - ANS✔✔-energy cannot be created or destroyed,
only converted into other forms
Spontaneous process - ANS✔✔-process that occurs naturally under certain
conditions
,nonspontaneous process - ANS✔✔-requires continual energy input from an
external source to occur
energy - ANS✔✔-capacity to supply heat or do work
internal energy (Delta U) - ANS✔✔-the total of all kinds of energy present in a
substance
Is water boiling at room temp spontaneous? - ANS✔✔-false
Is snow falling towards ground spontaneous? - ANS✔✔-true
are molecules from a cologne or perfume distributing throughout a room
spontaneous? - ANS✔✔-true
Describe how energy and matter can be dispersed during a spontaneous
process. Then, identify how energy and matter are specifically dispersed in the
following example:
An ice cube melts on a table. - ANS✔✔-energy is redistrubuted from areas of
greater energy to areas of lesser energy or energy is converted from one form
to another. matter is redistributed to form a uniform dispersal of particles or
matter is moved from one location to another.
Heat energy is gained by the water molecules and lost by the surroundings in
the room. The water molecules move farther apart as they go from a solid state
to a liquid state.
,Entropy (S) - ANS✔✔-the measure of a systems thermal energy per unit
temperature that is unavailable for doing useful work.
Reversible process - ANS✔✔-the direction can be changed or reversed. there is
a forward direction (towards right) and a reverse direction (towards left)
irreversible process - ANS✔✔-the system and its surroundings do not return to
their original condition after initiation
Calculate the change in entropy in a process occurring at 250 K with reversible
heat measured at 2400 J. Calculate your answer to 3 significant figures and
report your answer with the appropriate units. - ANS✔✔-Delta S = (q rev) / T
Delta S = (2400 J) / 250 K
Delta S = 9.60 J/K
Define, using your own words, microstates and their relationship to entropy -
ANS✔✔-microstates are a specific configuration of all the locations and
energies of the atoms or molecules that make up a system. Increasing number
of microstates means increasing entropy
Calculate the amount of entropy in a process where there are a) 2 microstates
and b) 25 microstates. Calculate your answer to 3 significant figures and report
your answer with the appropriate units. - ANS✔✔-Equation: S = k ln W
a.) S = (1.38 x 10^23 J/K) ln 2 = 9.57 x 10^24 J/K
b.) S = (1.38 x 10^23 J/K) ln 25 = 4.44 x 10^23 J/K
, List the general factors that can be used to predict the sign of entropy -
ANS✔✔-Number of particles
Number of microstates
Physical state (solid<liquid<gas)
Temperature
Atomic and molecular weight
Number of atoms in a molecule
Purity of a substance
Number of substances in a mixture
Summarize using your own words and any relevant examples, the 2nd and 3rd
laws of thermodynamics. - ANS✔✔-2nd law of thermodynamics - All
spontaneous changes cause an increase in the entropy of the universe.
3rd law of thermodynamics - The entropy of a pure, perfect crystalline
substance at 0 K is zero.
Complete the following table to summarize the relationships between ΔSuniv,
ΔG, and spontaneity. - ANS✔✔-ΔSuniv > 0
ΔG < 0
spontaneous
ΔSuniv < 0
ΔG > 0
nonspontaneous
STUDY GUIDE. // GRADED A+ // NEWEST EXAM STUDY
GUIDE // 2025 UPDATE
NEW!!! NEW!!! NEW!!!
MODULE 1
heat (q) - ANS✔✔-the transfer of thermal energy between two bodies at diff
temps
work (w) - ANS✔✔-transfer of mechanical energy causing matter to move
against an opposing force
potential energy - ANS✔✔-energy an object has because of its relative position
kinetic energy - ANS✔✔-the energy that an object possesses because of its
motion
1st law of thermodynamics - ANS✔✔-energy cannot be created or destroyed,
only converted into other forms
Spontaneous process - ANS✔✔-process that occurs naturally under certain
conditions
,nonspontaneous process - ANS✔✔-requires continual energy input from an
external source to occur
energy - ANS✔✔-capacity to supply heat or do work
internal energy (Delta U) - ANS✔✔-the total of all kinds of energy present in a
substance
Is water boiling at room temp spontaneous? - ANS✔✔-false
Is snow falling towards ground spontaneous? - ANS✔✔-true
are molecules from a cologne or perfume distributing throughout a room
spontaneous? - ANS✔✔-true
Describe how energy and matter can be dispersed during a spontaneous
process. Then, identify how energy and matter are specifically dispersed in the
following example:
An ice cube melts on a table. - ANS✔✔-energy is redistrubuted from areas of
greater energy to areas of lesser energy or energy is converted from one form
to another. matter is redistributed to form a uniform dispersal of particles or
matter is moved from one location to another.
Heat energy is gained by the water molecules and lost by the surroundings in
the room. The water molecules move farther apart as they go from a solid state
to a liquid state.
,Entropy (S) - ANS✔✔-the measure of a systems thermal energy per unit
temperature that is unavailable for doing useful work.
Reversible process - ANS✔✔-the direction can be changed or reversed. there is
a forward direction (towards right) and a reverse direction (towards left)
irreversible process - ANS✔✔-the system and its surroundings do not return to
their original condition after initiation
Calculate the change in entropy in a process occurring at 250 K with reversible
heat measured at 2400 J. Calculate your answer to 3 significant figures and
report your answer with the appropriate units. - ANS✔✔-Delta S = (q rev) / T
Delta S = (2400 J) / 250 K
Delta S = 9.60 J/K
Define, using your own words, microstates and their relationship to entropy -
ANS✔✔-microstates are a specific configuration of all the locations and
energies of the atoms or molecules that make up a system. Increasing number
of microstates means increasing entropy
Calculate the amount of entropy in a process where there are a) 2 microstates
and b) 25 microstates. Calculate your answer to 3 significant figures and report
your answer with the appropriate units. - ANS✔✔-Equation: S = k ln W
a.) S = (1.38 x 10^23 J/K) ln 2 = 9.57 x 10^24 J/K
b.) S = (1.38 x 10^23 J/K) ln 25 = 4.44 x 10^23 J/K
, List the general factors that can be used to predict the sign of entropy -
ANS✔✔-Number of particles
Number of microstates
Physical state (solid<liquid<gas)
Temperature
Atomic and molecular weight
Number of atoms in a molecule
Purity of a substance
Number of substances in a mixture
Summarize using your own words and any relevant examples, the 2nd and 3rd
laws of thermodynamics. - ANS✔✔-2nd law of thermodynamics - All
spontaneous changes cause an increase in the entropy of the universe.
3rd law of thermodynamics - The entropy of a pure, perfect crystalline
substance at 0 K is zero.
Complete the following table to summarize the relationships between ΔSuniv,
ΔG, and spontaneity. - ANS✔✔-ΔSuniv > 0
ΔG < 0
spontaneous
ΔSuniv < 0
ΔG > 0
nonspontaneous
