PORTAGE LEARNING CHEM 104
MODULE 1
PRACTICE EXAM QUESTIONS
WITH CORRECT DETAILED
ANSWERS | ALREADY GRADED
A+<RECENT VERSION>
1) Spontaneous process - answer process that occurs naturally under
certain conditions
2) nonspontaneous process - answer requires continual energy input from
an external source to occur
3) energy - answer capacity to supply heat or do work
4) heat (q) - answer the transfer of thermal energy between two bodies at
diff temps
5) work (w) - answer transfer of mechanical energy causing matter to
move against an opposing force
6) potential energy - answer energy an object has because of its relative
position
,7) kinetic energy - answer the energy that an object possesses because of
its motion
8) 1st law of thermodynamics - answer energy cannot be created or
destroyed, only converted into other forms
9) internal energy (delta u) - answer the total of all kinds of energy
present in a substance
10) is water boiling at room temp spontaneous? - answer false
11) is snow falling towards ground spontaneous? - answer true
12) are molecules from a cologne or perfume distributing throughout a
room spontaneous? - answer 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:
13) An ice cube melts on a table. - answer 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.
14) 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) - answer the measure
of a systems thermal energy per unit temperature that is unavailable for
doing useful work.
,15) reversible process - answer the direction can be changed or
reversed. There is a forward direction (towards right) and a reverse
direction (towards left)
16) irreversible process - answer the system and its surroundings do
not return to their original condition after initiation
17) 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. - answer
delta s = (q rev) / t
Delta s = (2400 j) / 250 k
Delta s = 9.60 j/k
18) define, using your own words, microstates and their relationship to
entropy - answer 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
19) 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. - answer
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
20) surface area/reaction rate - answer increase, increased surface
area of particles increases reaction rate because solids only react at their
surfaces (grinding solid into fine powder)
, 21) concentration/reaction rate - answer increase, provides more
reacting particles to undergo reaction
22) reaction rate - answer increase in molar concentration of
product per unit of time or the decrease in molar concentration per unit of
time
23) reaction rate units - answer moles per liter per second (mol/l*s)
24) reaction rate equation - answer change in concentration/change
in time
(products=positive, reactants=add negative sign)
25) average rate - answer determined by using initial and final
concentrations and initial and final times so that the result measures the
rate over the entire reaction
26) instantaneous rate - answer the change in concentration of
reactants (or products) divided by a very short period of time
27) instantaneous rate decreases... - answer decreases, as reaction
proceeds, concentration of reactant becomes smaller due to consumption
of reactants as reaction takes place
28) early instantaneous rate - answer the change in concentration of
reactants (or products) divided by a very short period of time near the
beginning of the reaction
MODULE 1
PRACTICE EXAM QUESTIONS
WITH CORRECT DETAILED
ANSWERS | ALREADY GRADED
A+<RECENT VERSION>
1) Spontaneous process - answer process that occurs naturally under
certain conditions
2) nonspontaneous process - answer requires continual energy input from
an external source to occur
3) energy - answer capacity to supply heat or do work
4) heat (q) - answer the transfer of thermal energy between two bodies at
diff temps
5) work (w) - answer transfer of mechanical energy causing matter to
move against an opposing force
6) potential energy - answer energy an object has because of its relative
position
,7) kinetic energy - answer the energy that an object possesses because of
its motion
8) 1st law of thermodynamics - answer energy cannot be created or
destroyed, only converted into other forms
9) internal energy (delta u) - answer the total of all kinds of energy
present in a substance
10) is water boiling at room temp spontaneous? - answer false
11) is snow falling towards ground spontaneous? - answer true
12) are molecules from a cologne or perfume distributing throughout a
room spontaneous? - answer 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:
13) An ice cube melts on a table. - answer 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.
14) 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) - answer the measure
of a systems thermal energy per unit temperature that is unavailable for
doing useful work.
,15) reversible process - answer the direction can be changed or
reversed. There is a forward direction (towards right) and a reverse
direction (towards left)
16) irreversible process - answer the system and its surroundings do
not return to their original condition after initiation
17) 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. - answer
delta s = (q rev) / t
Delta s = (2400 j) / 250 k
Delta s = 9.60 j/k
18) define, using your own words, microstates and their relationship to
entropy - answer 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
19) 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. - answer
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
20) surface area/reaction rate - answer increase, increased surface
area of particles increases reaction rate because solids only react at their
surfaces (grinding solid into fine powder)
, 21) concentration/reaction rate - answer increase, provides more
reacting particles to undergo reaction
22) reaction rate - answer increase in molar concentration of
product per unit of time or the decrease in molar concentration per unit of
time
23) reaction rate units - answer moles per liter per second (mol/l*s)
24) reaction rate equation - answer change in concentration/change
in time
(products=positive, reactants=add negative sign)
25) average rate - answer determined by using initial and final
concentrations and initial and final times so that the result measures the
rate over the entire reaction
26) instantaneous rate - answer the change in concentration of
reactants (or products) divided by a very short period of time
27) instantaneous rate decreases... - answer decreases, as reaction
proceeds, concentration of reactant becomes smaller due to consumption
of reactants as reaction takes place
28) early instantaneous rate - answer the change in concentration of
reactants (or products) divided by a very short period of time near the
beginning of the reaction
