CHEM 101 ACTUAL EXAM QUESTIONS AND
CORRECT DETAILED ANSWERS ALREADY
GRADED A+ (NEWEST VERSION)
Which of the following is an example of reactant concentration affecting the rate of a
reaction?
Select the correct answer below:
A wooden table burns more quickly in a fire than an iron headboard.
Five 4-inch diameter saplings burn more rapidly than a 20-inch tree of the same height.
Phosphorus burns much more rapidly in an atmosphere of pure oxygen than in air,
which is about 21% oxygen.
Food spoils more quickly on a kitchen counter than in a refrigerator. - Answer ✔
Phosphorus burns much more rapidly in an atmosphere of pure oxygen than in air,
which is about 21% oxygen.
Which is an example of concentration affecting the rate of reaction? - Answer ✔ a
solution containing two moles of each reactant has a faster instantaneous rate of
reaction than a solution of the same volume with only one mole of each reactant
An increase in temperature of ten degrees Celsius will have what effect on the rate? -
Answer ✔ depends on the reaction
Identify the options below that decrease the rate of a reaction. (select all that apply) -
Answer ✔ Decreasing the temperature of an endothermic reaction
Decreasing the concentration of a second order reactant
All of the following are examples of the temperature of reactants affecting the rate of a
reaction except: - Answer ✔ Phosphorus burns much more rapidly in an atmosphere of
pure oxygen than in air.
Which of the following actions increases the rate of a chemical reaction? (select all that
apply) - Answer ✔ adding a catalyst
lowering the activation energy
increasing the concentration of a first order reactant
increasing the temperature
Which is an example of temperature affecting the rate of reaction? - Answer ✔ a
reaction proceeds more quickly in the laboratory when placed over a Bunsen burner
A catalyst will- - Answer ✔ reduce the activation energy of a reaction
The structure in a reaction that has the highest potential energy is the:
, Select the correct answer below:
reactant
product
transition state
depends on the reaction - Answer ✔ transition state
Which description best fits the definition of activated complex? - Answer ✔ An activated
complex is an unstable combination of reactant species representing the highest energy
state of a reaction system.
Which of the following decreases the rate of a reaction?
Select the correct answer below:
Decreasing the concentration of a reactant that does not appear in the rate law
Heating up the reaction vessel on a hot plate
Taking a break after continuously stirring a very slow reaction for half an hour
Decreasing the concentration of a first order reactant - Answer ✔ Decreasing the
concentration of a first order reactant
Which of the following will burn the fastest?
Select the correct answer below:
A 2-pound log at 50∘C
A 2-pound log at 0∘C
A 2-pound log at room temperature
Each will react at the same rate. - Answer ✔ A 2-pound log at 50∘C
The relative numbers of reactants and products are represented by: - Answer ✔
coefficients
The correct order, from slowest to fastest, according to the rate of reaction of each with
sulfuric acid is: _______.
Select the correct answer below:
a 5-pound iron pipe; 5 pounds of iron shavings; 5 pounds of iron powder; a 5-pound iron
cube
a 5-pound iron cube; a 5-pound iron pipe; 5 pounds of iron shavings; 5 pounds of iron
powder
a 5-pound iron cube; 5 pounds of iron shavings; a 5-pound iron pipe; 5 pounds of iron
powder
a 5-pound iron pipe; 5 pounds of iron powder; 5 pounds of iron shavings; a 5-pound iron
cube - Answer ✔ a 5-pound iron cube; a 5-pound iron pipe; 5 pounds of iron shavings; 5
pounds of iron powder
A catalyst lowers the activation energy of a reaction by: - Answer ✔ providing an
alternate pathway or mechanism
CORRECT DETAILED ANSWERS ALREADY
GRADED A+ (NEWEST VERSION)
Which of the following is an example of reactant concentration affecting the rate of a
reaction?
Select the correct answer below:
A wooden table burns more quickly in a fire than an iron headboard.
Five 4-inch diameter saplings burn more rapidly than a 20-inch tree of the same height.
Phosphorus burns much more rapidly in an atmosphere of pure oxygen than in air,
which is about 21% oxygen.
Food spoils more quickly on a kitchen counter than in a refrigerator. - Answer ✔
Phosphorus burns much more rapidly in an atmosphere of pure oxygen than in air,
which is about 21% oxygen.
Which is an example of concentration affecting the rate of reaction? - Answer ✔ a
solution containing two moles of each reactant has a faster instantaneous rate of
reaction than a solution of the same volume with only one mole of each reactant
An increase in temperature of ten degrees Celsius will have what effect on the rate? -
Answer ✔ depends on the reaction
Identify the options below that decrease the rate of a reaction. (select all that apply) -
Answer ✔ Decreasing the temperature of an endothermic reaction
Decreasing the concentration of a second order reactant
All of the following are examples of the temperature of reactants affecting the rate of a
reaction except: - Answer ✔ Phosphorus burns much more rapidly in an atmosphere of
pure oxygen than in air.
Which of the following actions increases the rate of a chemical reaction? (select all that
apply) - Answer ✔ adding a catalyst
lowering the activation energy
increasing the concentration of a first order reactant
increasing the temperature
Which is an example of temperature affecting the rate of reaction? - Answer ✔ a
reaction proceeds more quickly in the laboratory when placed over a Bunsen burner
A catalyst will- - Answer ✔ reduce the activation energy of a reaction
The structure in a reaction that has the highest potential energy is the:
, Select the correct answer below:
reactant
product
transition state
depends on the reaction - Answer ✔ transition state
Which description best fits the definition of activated complex? - Answer ✔ An activated
complex is an unstable combination of reactant species representing the highest energy
state of a reaction system.
Which of the following decreases the rate of a reaction?
Select the correct answer below:
Decreasing the concentration of a reactant that does not appear in the rate law
Heating up the reaction vessel on a hot plate
Taking a break after continuously stirring a very slow reaction for half an hour
Decreasing the concentration of a first order reactant - Answer ✔ Decreasing the
concentration of a first order reactant
Which of the following will burn the fastest?
Select the correct answer below:
A 2-pound log at 50∘C
A 2-pound log at 0∘C
A 2-pound log at room temperature
Each will react at the same rate. - Answer ✔ A 2-pound log at 50∘C
The relative numbers of reactants and products are represented by: - Answer ✔
coefficients
The correct order, from slowest to fastest, according to the rate of reaction of each with
sulfuric acid is: _______.
Select the correct answer below:
a 5-pound iron pipe; 5 pounds of iron shavings; 5 pounds of iron powder; a 5-pound iron
cube
a 5-pound iron cube; a 5-pound iron pipe; 5 pounds of iron shavings; 5 pounds of iron
powder
a 5-pound iron cube; 5 pounds of iron shavings; a 5-pound iron pipe; 5 pounds of iron
powder
a 5-pound iron pipe; 5 pounds of iron powder; 5 pounds of iron shavings; a 5-pound iron
cube - Answer ✔ a 5-pound iron cube; a 5-pound iron pipe; 5 pounds of iron shavings; 5
pounds of iron powder
A catalyst lowers the activation energy of a reaction by: - Answer ✔ providing an
alternate pathway or mechanism
