Question 1

A reaction with an activation energy,Ea = 51.2 kJ/mol will proceed ________ times faster when the temperature is raised from 20 °C to 30 °C.

Accepted Answer

Question 2

A gas molecule at 298 K and 1 atm pressure undergoes a collision with another gas molecule approximately every ________ seconds.

Accepted Answer

A) 10-15 
B) 10-9 
C) 10-6 
D) 10-3 
A) 10-15 
B) 10-9 
C) 10-6 
D) 10-3

Question 3

The following reaction is first order in A and first order in B:
A + B → Products Rate = k[A][B]
What is the rate constant k of this reaction in vessel (b)relative to the rate constant k of this reaction in vessel (a)? Each vessel has the same volume.Shaded spheres represent A molecules,and unshaded spheres represent B molecules.

Accepted Answer

A) rate constant k in vessel (b)/rate constant k in vessel (a)= 1:2 
B) rate constant k in vessel (b)/rate constant k in vessel (a)= 1:1 
C) rate constant k in vessel (b)/rate constant k in vessel (a)= 2:1 
D) rate constant k in vessel (b)/rate constant k in vessel (a)= 4:1 
A) rate constant k in vessel (b)/rate constant k in vessel (a)= 1:2 
B) rate constant k in vessel (b)/rate constant k in vessel (a)= 1:1 
C) rate constant k in vessel (b)/rate constant k in vessel (a)= 2:1 
D) rate constant k in vessel (b)/rate constant k in vessel (a)= 4:1

Question 4

The first-order isomerization reaction: cyclopropane → propene,has a rate constant of
1)10 × 10-4s-1 at 470°C and 5.70 × 10-4s-1 at 500°C.What is the activation energy,Ea,for the reaction?

Accepted Answer

A) 46 kJ/mol 
B) 110 kJ/mol 
C) 260 kJ/mol 
D) 380 kJ/mol 
A) 46 kJ/mol 
B) 110 kJ/mol 
C) 260 kJ/mol 
D) 380 kJ/mol

Question 5

Iodine-123,used in thyroid therapy,has a half-life of 13.27 hours.How many half-lives are required for a 160 mg sample of iodine-123 to decay to 5.0 mg?

Accepted Answer

A) 0)031 
B) 1)0 
C) 5)0 
D) 32 
A) 0)031 
B) 1)0 
C) 5)0 
D) 32

Question 6

The reaction that occurs in a Breathalyzer,a device used to determine the alcohol level in a person's bloodstream,is given below.If the rate of appearance of Cr2(SO4)3 is 1.64 mol/min at a particular moment,what is the rate of disappearance of C2H6O at that moment?

Accepted Answer

A) 0)547 mol/min 
B) 1)09 mol/min 
C) 2)46 mol/min 
D) 4)92 mol/min 
A) 0)547 mol/min 
B) 1)09 mol/min 
C) 2)46 mol/min 
D) 4)92 mol/min

Question 7

A reaction is second order in NO and first order in O2 has a rate constant,k = 1.4 × 104 M-2s-1.What is the initial rate of reaction when the concentrations of NO and O2 are 0.015 M and 0.030 M,respectively?

Accepted Answer

Question 8

Given the following hypothetical reaction: 2 E(g)+ F(g)+ G(g)→ products.
If the rate law is: Rate = k[E]2[F]-1,what is the order of reaction with respect to E?

Accepted Answer

A) zero 
B) first 
C) second 
D) third 
A) zero 
B) first 
C) second 
D) third

Question 9

The following reaction is first order,C2H6 → 2 CH3.If the rate constant is equal to 5.5 × 10-4 s-1 at 1000 K,how long will it take for 0.35 mol of C2H6 in a 1.00 L container to decrease to 0.20 mol in the same container?

Accepted Answer

A) 4)5 min 
B) 17 min 
C) 53 min 
D) 65 min 
A) 4)5 min 
B) 17 min 
C) 53 min 
D) 65 min

Question 10

The slowest step in a reaction mechanism is called the ________ step.

Accepted Answer

A) activation 
B) elementary 
C) rate law 
D) rate-determining 
A) activation 
B) elementary 
C) rate law 
D) rate-determining

Question 11

The aquation of tris(1,10-phenanthroline)iron(II)in acid solution takes place according to the equation:
Fe(phen)32+ + 3 H3O+ + 3 H2O → Fe(H2O)62+ + 3 phenH+
If the activation energy is 126 kJ/mol and frequency factor is 8.62 × 1017 s-1,at what temperature is the rate constant equal to 3.63 × 10-3 s-1 for the first-order reaction?

Accepted Answer

A) 0°C 
B) 36°C 
C) 50°C 
D) 94°C 
A) 0°C 
B) 36°C 
C) 50°C 
D) 94°C

Question 12

Platinum in the catalytic converter of an automobile catalyzes the conversion of CO to CO2 is an example of a ________ (heterogeneous,homogeneous)catalyst.

Accepted Answer

Question 13

Molecular hydrogen can be made from methane gas by the reaction below.How is the rate of disappearance of CH4 related to the rate of appearance of H2?  
= ?
CH4 (g)+ H2O (l)→ CO (g)+ 3H2 (g)

Accepted Answer

A)    
B)    
C)    
D) none of these 
A)    
B)    
C)    
D) none of these

Question 14

A mechanism for a naturally occurring reaction that destroys ozone is:
Step 1: O3(g)+ HO(g)→ HO2(g)+ O2(g)
Step 2: HO2(g)+ O(g)→ HO(g)+ O2(g)
Which species is a catalyst and what type of catalysis is occurring?

Accepted Answer

A) HO,homogeneous 
B) HO,heterogeneous 
C) HO2,homogeneous 
D) HO2,heterogeneous 
A) HO,homogeneous 
B) HO,heterogeneous 
C) HO2,homogeneous 
D) HO2,heterogeneous

Question 15

A gaseous compound,C,undergoes catalytic decomposition at an initial rate of 0.45 M/s when
[C]o = 3.0 × 10-3 M and 0.45 M/s when [C]o = 9.0 × 10-3 M.Therefore,this is a ________ order reaction.

Accepted Answer

Question 16

The following set of data was obtained by the method of initial rates for the reaction:
S2O82-(aq)+ 3 I-(aq)→ 2 SO42-(aq)+ I3-(aq)
What is the initial rate when S2O82- is 0.15 M and I- is 0.15 M?

Accepted Answer

A) 4)10 × 10-6 M s-1 
B) 8)10 × 10-3 M s-1 
C) 1)22 × 10-2 M s-1 
D) 5)40 × 10-2 M s-1 
A) 4)10 × 10-6 M s-1 
B) 8)10 × 10-3 M s-1 
C) 1)22 × 10-2 M s-1 
D) 5)40 × 10-2 M s-1

Question 17

The decomposition of dinitrogen pentoxide is described by the chemical equation
2 N2O5(g)→ 4 NO2(g)+ O2(g)
If the rate of disappearance of N2O5 is equal to 1.60 mol/min at a particular moment,what is the rate of appearance of NO2 at that moment?

Accepted Answer

A) 0)800 mol/min 
B) 1)60 mol/min 
C) 3)20 mol/min 
D) 6)40 mol/min 
A) 0)800 mol/min 
B) 1)60 mol/min 
C) 3)20 mol/min 
D) 6)40 mol/min

Question 18

The following reaction is second order in A and first order in B:
A + B → Products Rate = k[A]2[B]
What is the initial rate of this reaction in vessel (b)relative to the initial rate of this reaction in vessel (a)? Each vessel has the same volume.Shaded spheres represent A molecules,and unshaded spheres represent B molecules present at the beginning of the reaction.

Accepted Answer

A) rate in vessel (b)/rate in vessel (a)= 1:2 
B) rate in vessel (b)/rate in vessel (a)= 1:1 
C) rate in vessel (b)/rate in vessel (a)= 2:1 
D) rate in vessel (b)/rate in vessel (a)= 4:1 
A) rate in vessel (b)/rate in vessel (a)= 1:2 
B) rate in vessel (b)/rate in vessel (a)= 1:1 
C) rate in vessel (b)/rate in vessel (a)= 2:1 
D) rate in vessel (b)/rate in vessel (a)= 4:1

Question 19

A three-step mechanism has been suggested for the formation of carbonyl chloride:
Step 1: Cl2 → 2 Cl
Step 2: Cl + CO → COCl
Step 3: COCl + Cl2 → COCl2 + Cl
Which species is an intermediate in the mechanism?

Accepted Answer

A) Cl 
B) CO 
C) COCl 
D) COCl2 
A) Cl 
B) CO 
C) COCl 
D) COCl2

Question 20

Consider the first-order decomposition of A molecules (shaded spheres)in two vessels of equal volume.What is the half-life of decomposition in vessel (b)relative to the half-life of decomposition in vessel (a)?

Accepted Answer

A) half-life in vessel (b)/half-life in vessel (a)= 4:1 
B) half-life in vessel (b)/half-life in vessel (a)= 2:1 
C) half-life in vessel (b)/half-life in vessel (a)= 3:2 
D) half-life in vessel (b)/half-life in vessel (a)= 1:1 
A) half-life in vessel (b)/half-life in vessel (a)= 4:1 
B) half-life in vessel (b)/half-life in vessel (a)= 2:1 
C) half-life in vessel (b)/half-life in vessel (a)= 3:2 
D) half-life in vessel (b)/half-life in vessel (a)= 1:1

A reaction with an activation energy,E_a = 51.2 kJ/mol will proceed ________ times faster when the temperature is raised from 20 °C to 30 °C.

A gas molecule at 298 K and 1 atm pressure undergoes a collision with another gas molecule approximately every ________ seconds.

The first-order isomerization reaction: cyclopropane → propene,has a rate constant of 1)10 × 10^-4s^-1 at 470°C and 5.70 × 10^-4s^-1 at 500°C.What is the activation energy,E_a,for the reaction?

Iodine-123,used in thyroid therapy,has a half-life of 13.27 hours.How many half-lives are required for a 160 mg sample of iodine-123 to decay to 5.0 mg?

The reaction that occurs in a Breathalyzer,a device used to determine the alcohol level in a person's bloodstream,is given below.If the rate of appearance of Cr₂(SO₄)₃ is 1.64 mol/min at a particular moment,what is the rate of disappearance of C₂H₆O at that moment?

A reaction is second order in NO and first order in O₂ has a rate constant,k = 1.4 × 10⁴ M^-2s^-1.What is the initial rate of reaction when the concentrations of NO and O₂ are 0.015 M and 0.030 M,respectively?

Given the following hypothetical reaction: 2 E(g)+ F(g)+ G(g)→ products. If the rate law is: Rate = k[E]²[F]^-1,what is the order of reaction with respect to E?

The following reaction is first order,C₂H₆ → 2 CH₃.If the rate constant is equal to 5.5 × 10^-4 s^-1 at 1000 K,how long will it take for 0.35 mol of C₂H₆ in a 1.00 L container to decrease to 0.20 mol in the same container?

The slowest step in a reaction mechanism is called the ________ step.

Platinum in the catalytic converter of an automobile catalyzes the conversion of CO to CO₂ is an example of a ________ (heterogeneous,homogeneous)catalyst.

Molecular hydrogen can be made from methane gas by the reaction below.How is the rate of disappearance of CH₄ related to the rate of appearance of H₂? = ? CH₄ (g)+ H₂O (l)→ CO (g)+ 3H₂ (g)

A mechanism for a naturally occurring reaction that destroys ozone is: Step 1: O₃(g)+ HO(g)→ HO₂(g)+ O₂(g) Step 2: HO₂(g)+ O(g)→ HO(g)+ O₂(g) Which species is a catalyst and what type of catalysis is occurring?

A gaseous compound,C,undergoes catalytic decomposition at an initial rate of 0.45 M/s when [C]_o = 3.0 × 10^-3 M and 0.45 M/s when [C]_o = 9.0 × 10^-3 M.Therefore,this is a ________ order reaction.

The following set of data was obtained by the method of initial rates for the reaction: S₂O₈^2-(aq)+ 3 I^-(aq)→ 2 SO₄^2-(aq)+ I₃^-(aq) What is the initial rate when S₂O₈^2- is 0.15 M and I^- is 0.15 M?

The decomposition of dinitrogen pentoxide is described by the chemical equation 2 N₂O₅(g)→ 4 NO₂(g)+ O₂(g) If the rate of disappearance of N₂O₅ is equal to 1.60 mol/min at a particular moment,what is the rate of appearance of NO₂ at that moment?

A three-step mechanism has been suggested for the formation of carbonyl chloride: Step 1: Cl₂ → 2 Cl Step 2: Cl + CO → COCl Step 3: COCl + Cl₂ → COCl₂ + Cl Which species is an intermediate in the mechanism?

Consider the first-order decomposition of A molecules (shaded spheres)in two vessels of equal volume.What is the half-life of decomposition in vessel (b)relative to the half-life of decomposition in vessel (a)?

Chemistry: Matter and Measurement

Atoms, molecules, and Ions

Formulas, equations, and Moles

Reactions in Aqueous Solutions

Periodicity and the Atomic Structure of Atoms

Ionic Bonds and Some Main-Group Chemistry

Covalent Bonds and Molecular Structure

Thermochemistry: Chemical Energy

Gases: Their Properties and Behavior

Liquids,solids,and Phase Changes

Solutions and Their Properties

Chemical Equilibrium

Aqueous Equilibria: Acids and Bases

Applications of Aqueous Equilibria

Thermodynamics: Entropy, free Energy, and Equilibrium

Electrochemistry

Hydrogen, oxygen, and Water

The Main-Group Elements

Transition Elements and Coordination Chemistry

Metals and Solid-State Materials

Nuclear Chemistry

Organic and Biological Chemistry

Filters

Exam 12: Chemical Kinetics

A reaction with an activation energy,Ea = 51.2 kJ/mol will proceed ________ times faster when the temperature is raised from 20 °C to 30 °C.

A gas molecule at 298 K and 1 atm pressure undergoes a collision with another gas molecule approximately every ________ seconds.

The first-order isomerization reaction: cyclopropane → propene,has a rate constant of 1)10 × 10-4s-1 at 470°C and 5.70 × 10-4s-1 at 500°C.What is the activation energy,Ea,for the reaction?

Iodine-123,used in thyroid therapy,has a half-life of 13.27 hours.How many half-lives are required for a 160 mg sample of iodine-123 to decay to 5.0 mg?

The reaction that occurs in a Breathalyzer,a device used to determine the alcohol level in a person's bloodstream,is given below.If the rate of appearance of Cr2(SO4)3 is 1.64 mol/min at a particular moment,what is the rate of disappearance of C2H6O at that moment?

A reaction is second order in NO and first order in O2 has a rate constant,k = 1.4 × 104 M-2s-1.What is the initial rate of reaction when the concentrations of NO and O2 are 0.015 M and 0.030 M,respectively?

Given the following hypothetical reaction: 2 E(g)+ F(g)+ G(g)→ products. If the rate law is: Rate = k[E]2[F]-1,what is the order of reaction with respect to E?

The following reaction is first order,C2H6 → 2 CH3.If the rate constant is equal to 5.5 × 10-4 s-1 at 1000 K,how long will it take for 0.35 mol of C2H6 in a 1.00 L container to decrease to 0.20 mol in the same container?

The slowest step in a reaction mechanism is called the ________ step.

Platinum in the catalytic converter of an automobile catalyzes the conversion of CO to CO2 is an example of a ________ (heterogeneous,homogeneous)catalyst.

Molecular hydrogen can be made from methane gas by the reaction below.How is the rate of disappearance of CH4 related to the rate of appearance of H2? = ? CH4 (g)+ H2O (l)→ CO (g)+ 3H2 (g)

A mechanism for a naturally occurring reaction that destroys ozone is: Step 1: O3(g)+ HO(g)→ HO2(g)+ O2(g) Step 2: HO2(g)+ O(g)→ HO(g)+ O2(g) Which species is a catalyst and what type of catalysis is occurring?

A gaseous compound,C,undergoes catalytic decomposition at an initial rate of 0.45 M/s when [C]o = 3.0 × 10-3 M and 0.45 M/s when [C]o = 9.0 × 10-3 M.Therefore,this is a ________ order reaction.

The following set of data was obtained by the method of initial rates for the reaction: S2O82-(aq)+ 3 I-(aq)→ 2 SO42-(aq)+ I3-(aq) What is the initial rate when S2O82- is 0.15 M and I- is 0.15 M?

The decomposition of dinitrogen pentoxide is described by the chemical equation 2 N2O5(g)→ 4 NO2(g)+ O2(g) If the rate of disappearance of N2O5 is equal to 1.60 mol/min at a particular moment,what is the rate of appearance of NO2 at that moment?

A three-step mechanism has been suggested for the formation of carbonyl chloride: Step 1: Cl2 → 2 Cl Step 2: Cl + CO → COCl Step 3: COCl + Cl2 → COCl2 + Cl Which species is an intermediate in the mechanism?

Consider the first-order decomposition of A molecules (shaded spheres)in two vessels of equal volume.What is the half-life of decomposition in vessel (b)relative to the half-life of decomposition in vessel (a)?

Chemistry: Matter and Measurement

Atoms, molecules, and Ions

Formulas, equations, and Moles

Reactions in Aqueous Solutions

Periodicity and the Atomic Structure of Atoms

Ionic Bonds and Some Main-Group Chemistry

Covalent Bonds and Molecular Structure

Thermochemistry: Chemical Energy

Gases: Their Properties and Behavior

Liquids,solids,and Phase Changes

Solutions and Their Properties

Chemical Equilibrium

Aqueous Equilibria: Acids and Bases

Applications of Aqueous Equilibria

Thermodynamics: Entropy, free Energy, and Equilibrium

Electrochemistry

Hydrogen, oxygen, and Water

The Main-Group Elements

Transition Elements and Coordination Chemistry

Metals and Solid-State Materials

Nuclear Chemistry

Organic and Biological Chemistry

Filters

A reaction with an activation energy,E_a = 51.2 kJ/mol will proceed ________ times faster when the temperature is raised from 20 °C to 30 °C.

The first-order isomerization reaction: cyclopropane → propene,has a rate constant of 1)10 × 10^-4s^-1 at 470°C and 5.70 × 10^-4s^-1 at 500°C.What is the activation energy,E_a,for the reaction?

The reaction that occurs in a Breathalyzer,a device used to determine the alcohol level in a person's bloodstream,is given below.If the rate of appearance of Cr₂(SO₄)₃ is 1.64 mol/min at a particular moment,what is the rate of disappearance of C₂H₆O at that moment?

A reaction is second order in NO and first order in O₂ has a rate constant,k = 1.4 × 10⁴ M^-2s^-1.What is the initial rate of reaction when the concentrations of NO and O₂ are 0.015 M and 0.030 M,respectively?

Given the following hypothetical reaction: 2 E(g)+ F(g)+ G(g)→ products. If the rate law is: Rate = k[E]²[F]^-1,what is the order of reaction with respect to E?

The following reaction is first order,C₂H₆ → 2 CH₃.If the rate constant is equal to 5.5 × 10^-4 s^-1 at 1000 K,how long will it take for 0.35 mol of C₂H₆ in a 1.00 L container to decrease to 0.20 mol in the same container?

Platinum in the catalytic converter of an automobile catalyzes the conversion of CO to CO₂ is an example of a ________ (heterogeneous,homogeneous)catalyst.

Molecular hydrogen can be made from methane gas by the reaction below.How is the rate of disappearance of CH₄ related to the rate of appearance of H₂? = ? CH₄ (g)+ H₂O (l)→ CO (g)+ 3H₂ (g)

A mechanism for a naturally occurring reaction that destroys ozone is: Step 1: O₃(g)+ HO(g)→ HO₂(g)+ O₂(g) Step 2: HO₂(g)+ O(g)→ HO(g)+ O₂(g) Which species is a catalyst and what type of catalysis is occurring?

A gaseous compound,C,undergoes catalytic decomposition at an initial rate of 0.45 M/s when [C]_o = 3.0 × 10^-3 M and 0.45 M/s when [C]_o = 9.0 × 10^-3 M.Therefore,this is a ________ order reaction.

The following set of data was obtained by the method of initial rates for the reaction: S₂O₈^2-(aq)+ 3 I^-(aq)→ 2 SO₄^2-(aq)+ I₃^-(aq) What is the initial rate when S₂O₈^2- is 0.15 M and I^- is 0.15 M?

The decomposition of dinitrogen pentoxide is described by the chemical equation 2 N₂O₅(g)→ 4 NO₂(g)+ O₂(g) If the rate of disappearance of N₂O₅ is equal to 1.60 mol/min at a particular moment,what is the rate of appearance of NO₂ at that moment?

A three-step mechanism has been suggested for the formation of carbonyl chloride: Step 1: Cl₂ → 2 Cl Step 2: Cl + CO → COCl Step 3: COCl + Cl₂ → COCl₂ + Cl Which species is an intermediate in the mechanism?