CEM 142 EXAM 3 MSU QUESTIONS AND
ANSWERS 2026 VERIFIED.
What do you know about reactions? (make a list) - ANS -Atoms are conserved. They are only
re-arranged.
-Properties of products are emergent (not a mixture of the reactants properties).
-Reactions can be classified by the type of reaction (how it occurs).
-Reactions are always accompanied by an energy change (can be exo and endo) that results
from changed in interactions (bonds and IMFs) in the reactants and products.
-Reactions are always accompanied by an entropy change.
What are the two main typed of reactions? - ANS -Acid-base
-Redox
*Always accompanied by a changed in entropy.
Can you predict the properties of products if you know the properties of the reactants?
A. Yes
B. No
C. It depends
D. I dont know - ANS -B
*Properties include smell, melting point, boiling point, and color.
For the reaction: A+B-->C
If A is yellow and B is blue, what color is C?
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,A. Yellow
B. Blue
C. Green
D. I dont know - ANS -D
*React NOT mix. C = completely new product.
What thermodynamic function tells you about how far a reaction will "go"?
A. Delta H
B. Delta S (system)
C. Delta G
D. None of these - ANS -C
*If (+) will NOT happen.
*If (-) WILL happen.
What thermodynamic function tells you about how fast a reaction will "go"?
A. Delta H
B. Delta S (system)
C. Delta G
D. None of these - ANS -D
*Delta H = energy change / only heat.
*Delta S = Number of possible arrangements in system.
*Delta G = How far the reaction will go.
Reactions can "go" both ____________ and _____________! The sign of __________ will tell
you whether a reaction will go forwards or backwards. - ANS -Forwards and Backwards.
-Delta G.
How fast a reaction goes depends on...? - ANS -Activation Energy.
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, Acid Base reaction are ____________. (speed). However, this does not mean that an Acid Base
reaction will go to...? - ANS -Fast.
-Completion.
HCl(g) +H2O--> H3O+(aq) +Cl-(aq)
This reaction occurs ______________ and only the ______________ are detectable in the
reaction mixture. - ANS -Immediately.
-Products.
If you dissolve 0.1 mol HCl in 1L solution-immediately the pH = ? However if you dissolve 0.1
mol acetic acid in 1L solution-immediately the pH =? - ANS -1.
-2.9.
Weak Acid Base Reaction are _______ but DO NOT go to ___________. - ANS -Fast.
-Completion.
Rusting-oxidation of Iron-tends to be slow (you would have to wait a while)-but if you leave it
long enough the reaction will...? - ANS -Go to completion.
The rate of a reaction has NOTHING to fo with the position of ____________. - ANS -
Equilibrium.
(How fast a reaction is has nothing to do with how far it goes.)
A rate is a ________ in something per unit of time. e.g. speed is miles per hour (miles/hr or
mph) or km/s. - ANS -Change.
If you travel 120 miles in 2 hours, your rate is...?
A. 120 mph
B. 60 mph
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ANSWERS 2026 VERIFIED.
What do you know about reactions? (make a list) - ANS -Atoms are conserved. They are only
re-arranged.
-Properties of products are emergent (not a mixture of the reactants properties).
-Reactions can be classified by the type of reaction (how it occurs).
-Reactions are always accompanied by an energy change (can be exo and endo) that results
from changed in interactions (bonds and IMFs) in the reactants and products.
-Reactions are always accompanied by an entropy change.
What are the two main typed of reactions? - ANS -Acid-base
-Redox
*Always accompanied by a changed in entropy.
Can you predict the properties of products if you know the properties of the reactants?
A. Yes
B. No
C. It depends
D. I dont know - ANS -B
*Properties include smell, melting point, boiling point, and color.
For the reaction: A+B-->C
If A is yellow and B is blue, what color is C?
@COPYRIGHT ALL RIGHTS RESERVED PAGE 1 OF 30
,A. Yellow
B. Blue
C. Green
D. I dont know - ANS -D
*React NOT mix. C = completely new product.
What thermodynamic function tells you about how far a reaction will "go"?
A. Delta H
B. Delta S (system)
C. Delta G
D. None of these - ANS -C
*If (+) will NOT happen.
*If (-) WILL happen.
What thermodynamic function tells you about how fast a reaction will "go"?
A. Delta H
B. Delta S (system)
C. Delta G
D. None of these - ANS -D
*Delta H = energy change / only heat.
*Delta S = Number of possible arrangements in system.
*Delta G = How far the reaction will go.
Reactions can "go" both ____________ and _____________! The sign of __________ will tell
you whether a reaction will go forwards or backwards. - ANS -Forwards and Backwards.
-Delta G.
How fast a reaction goes depends on...? - ANS -Activation Energy.
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, Acid Base reaction are ____________. (speed). However, this does not mean that an Acid Base
reaction will go to...? - ANS -Fast.
-Completion.
HCl(g) +H2O--> H3O+(aq) +Cl-(aq)
This reaction occurs ______________ and only the ______________ are detectable in the
reaction mixture. - ANS -Immediately.
-Products.
If you dissolve 0.1 mol HCl in 1L solution-immediately the pH = ? However if you dissolve 0.1
mol acetic acid in 1L solution-immediately the pH =? - ANS -1.
-2.9.
Weak Acid Base Reaction are _______ but DO NOT go to ___________. - ANS -Fast.
-Completion.
Rusting-oxidation of Iron-tends to be slow (you would have to wait a while)-but if you leave it
long enough the reaction will...? - ANS -Go to completion.
The rate of a reaction has NOTHING to fo with the position of ____________. - ANS -
Equilibrium.
(How fast a reaction is has nothing to do with how far it goes.)
A rate is a ________ in something per unit of time. e.g. speed is miles per hour (miles/hr or
mph) or km/s. - ANS -Change.
If you travel 120 miles in 2 hours, your rate is...?
A. 120 mph
B. 60 mph
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