Question 1

In the reaction, 2N2O $\rarr$ 2N2 + O2, oxygen and nitrogen gases are formed at the same rate (mol/L·s).

Accepted Answer

A) True 
 B)False  False

Question 2

For what order reaction does the half-life get longer as the initial concentration increases?

Accepted Answer

A) zero order 
B) first order 
C) second order 
D) none of them because half-life is always independent of the initial concentration 
A) zero order 
B) first order 
C) second order 
D) none of them because half-life is always independent of the initial concentration A

Question 3

The rate constant of a first-order reaction, A $\rarr$ products, can be determined from a graph of ln[A] versus t.

Accepted Answer

A) True 
 B)False  True

Question 4

For the chemical reaction A $\rarr$ B + C, a plot of [A]t versus time is found to give a straight line with a negative slope.What is the order of reaction with respect to A?

Accepted Answer

A) zero 
B) first 
C) second 
D) third 
E) Such a plot cannot reveal the order of the reaction. 
A) zero 
B) first 
C) second 
D) third 
E) Such a plot cannot reveal the order of the reaction.

Question 5

Nitrogen pentoxide decomposes by a first-order process yielding N2O4 and oxygen.
2N2O5 $\rarr$2N2O4 + O2
 At a given temperature, the half-life of N2O5 is 0.90 hr.What is the first-order rate constant for N2O5 decomposition?

Accepted Answer

Question 6

A certain reaction A $\rarr$ products is second order with respect to A with a rate constant, k, 0.122 M-1min-1.Starting with [A]o = 1.01M, how many seconds will it take for A to reach a concentration of 0.750M?

Accepted Answer

A) 2.81 s 
B) 14.9 s 
C) 893 s 
D) 169 s 
E) 128 s 
A) 2.81 s 
B) 14.9 s 
C) 893 s 
D) 169 s 
E) 128 s

Question 7

The reaction 2A + B $\rarr$ products is second order with respect to A and zero-order with respect to B.Starting with 0.135 M of A, what is the concentration of A after 35 min if the rate constant is 0.11 M-1s-1?

Accepted Answer

Question 8

The activation energy for a certain reaction is 113 kJ/mol.By what factor (how many times)will the rate constant increase when the temperature is raised from 310 K to 325 K?

Accepted Answer

The answer of The activation energy for a certain reaction...

Question 9

For the first-order reaction, A $\rarr$ products, if half of the initial concentration of A reacts in 20 min, then the remaining half will completely react in the next 20 min.

Accepted Answer

A) True 
 B)False

Question 10

Nitric oxide gas (NO)reacts with chlorine gas according to the chemical equation given below. NO +   Cl2 $\rarr$ NOCl
The following initial rates of reaction have been measured for the given reagent concentrations.   Which of the following is the rate law (rate equation)for this reaction?

Accepted Answer

A) rate = k[NO] 
B) rate = k[NO][Cl2]1/2 
C) rate = k[NO][Cl2] 
D) rate = k[NO]2[Cl2] 
E) rate = k[NO]2[Cl2]2 
A) rate = k[NO] 
B) rate = k[NO][Cl2]1/2 
C) rate = k[NO][Cl2] 
D) rate = k[NO]2[Cl2] 
E) rate = k[NO]2[Cl2]2

Question 11

The reaction A + 2B $\rarr$ products was found to follow the rate law: rate = k[A]2[B].Predict by what factor the rate of reaction will increase when the concentration of A is doubled, the concentration of B is tripled, and the temperature remains constant.

Accepted Answer

A) 5 
B) 6 
C) 12 
D) 18 
E) None of these. 
A) 5 
B) 6 
C) 12 
D) 18 
E) None of these.

Question 12

The activation energy of a certain uncatalyzed reaction is 64 kJ/mol.In the presence of a catalyst, the Ea is 55 kJ/mol.How many times faster is the catalyzed than the uncatalyzed reaction at 400°C? Assume that the frequency factor remains the same.

Accepted Answer

A) 5.0 times 
B) 1.16 times 
C) 15 times 
D) 2.0 times 
E) 0.2 times 
A) 5.0 times 
B) 1.16 times 
C) 15 times 
D) 2.0 times 
E) 0.2 times

Question 13

A certain reaction, reaction A $\rarr$ products, is first order with respect to A.Starting with [A] = 0.250M, it takes 45 min to reduce the concentration of A to 0.110M.What is its rate constant for this reaction?

Accepted Answer

A) 7.9 x 10-3 min-1 
B) 1.1 x 10-1 min-1 
C) 3.0 x 10-4 min-1 
D) 1.8 x 10-2 min-1 
E) 3.1 x 10-3 min-1 
A) 7.9 x 10-3 min-1 
B) 1.1 x 10-1 min-1 
C) 3.0 x 10-4 min-1 
D) 1.8 x 10-2 min-1 
E) 3.1 x 10-3 min-1

Question 14

Hydrogen peroxide decomposes to water and oxygen gas, and the activation energy for this process is 42 kJ/mol.The hydrogen peroxide formed in biological processes is harmful to tissue, but the enzyme catalase catalyzes the decomposition of hydrogen peroxide by lowering the activation energy to 7.0 kJ/mol.Assuming the frequency factor is the same for both processes and independent of temperature, calculate the temperature required for the uncatalyzed decomposition to proceed at the same rate as the enzyme-catalyzed decomposition at 37°C (normal human body temperature).Is this a reasonable temperature for a biological organism?

Accepted Answer

1600°C; no

Question 15

At a certain temperature, the data below were collected for the reaction below.
2ICl + H2 $\rarr$I2 + 2HCl.
Determine the rate law for the reaction.

Accepted Answer

Question 16

Which of the following elementary steps is bimolecular?

Accepted Answer

A) 2A + B $\rarr$ A2B 
B) 3B $\rarr$ B2 + B 
C) A + B + C $\rarr$ AB + C 
D) A2 $\rarr$2A 
E) 2A $\rarr$A2 
A) 2A + B $\rarr$ A2B 
B) 3B $\rarr$ B2 + B 
C) A + B + C $\rarr$ AB + C 
D) A2 $\rarr$2A 
E) 2A $\rarr$A2

Question 17

The peroxodisulfate ion can oxidize iodide ions to iodine according to the balanced equation S2O82- + 2I - $\rarr$ 2SO42- + I2.
The reaction is catalyzed by certain chemical species.Identify the catalyst in the following mechanism:
Step 1: Fe3+ + 2I - $\rarr$ Fe2+ + I2
 step 2: S2O82-  + Fe2+ $\rarr$ 2SO42-  + Fe3+

Accepted Answer

A) Fe3+ 
B) I - 
C) S2O82- 
D) Fe2+ 
E) SO42- 
A) Fe3+ 
B) I - 
C) S2O82- 
D) Fe2+ 
E) SO42-

Question 18

A reaction was experimentally determined to follow the rate law, Rate = k[A]2 where k = 0.456 s-1M-1.Starting with [A]o = 0.500 M, how many seconds will it take for [A]t = 0.250 M?

Accepted Answer

A) 2.85 x 10-2 s 
B) 1.14 x 10-1 s 
C) 1.52 s 
D) 4.39 s 
E) 5.48x10-1 s 
A) 2.85 x 10-2 s 
B) 1.14 x 10-1 s 
C) 1.52 s 
D) 4.39 s 
E) 5.48x10-1 s

Question 19

The activation energy for the reaction CH3CO $\rarr$CH3 + CO is 71 kJ/mol.How many times greater is the rate constant for this reaction at 170°C than at 150°C?

Accepted Answer

A) 0.40 
B) 1.1 
C) 2.5 
D) 4.0 
E) 5.0 
A) 0.40 
B) 1.1 
C) 2.5 
D) 4.0 
E) 5.0

Question 20

At a particular temperature the first-order gas-phase reaction 2N2O5 $\rarr$ 2N2O4 + O2 has a half-life for the disappearance of dinitrogen pentoxide of 3240 s.If 1.00 atm of N2O5 is introduced into an evacuated 5.00 L flask, what will be the total pressure of the gases in the flask after 1.50 hours?

Accepted Answer

A) 0.685 atm 
B) 1.00 atm 
C) 0.315 atm 
D) 1.68 atm 
E) 1.34 atm 
A) 0.685 atm 
B) 1.00 atm 
C) 0.315 atm 
D) 1.68 atm 
E) 1.34 atm

In the reaction, 2N₂O $\rarr$ 2N₂ + O₂, oxygen and nitrogen gases are formed at the same rate (mol/L·s).

For what order reaction does the half-life get longer as the initial concentration increases?

The rate constant of a first-order reaction, A $\rarr$ products, can be determined from a graph of ln[A] versus t.

For the chemical reaction A $\rarr$ B + C, a plot of [A]_t versus time is found to give a straight line with a negative slope.What is the order of reaction with respect to A?

Nitrogen pentoxide decomposes by a first-order process yielding N₂O₄ and oxygen. 2N₂O₅ $\rarr$ 2N₂O₄ + O₂ At a given temperature, the half-life of N₂O₅ is 0.90 hr.What is the first-order rate constant for N₂O₅ decomposition?

A certain reaction A $\rarr$ products is second order with respect to A with a rate constant, k, 0.122 M^-1min^-1.Starting with [A]_o = 1.01M, how many seconds will it take for A to reach a concentration of 0.750M?

The reaction 2A + B $\rarr$ products is second order with respect to A and zero-order with respect to B.Starting with 0.135 M of A, what is the concentration of A after 35 min if the rate constant is 0.11 M^-1s^-1?

The activation energy for a certain reaction is 113 kJ/mol.By what factor (how many times)will the rate constant increase when the temperature is raised from 310 K to 325 K?

For the first-order reaction, A $\rarr$ products, if half of the initial concentration of A reacts in 20 min, then the remaining half will completely react in the next 20 min.

The reaction A + 2B $\rarr$ products was found to follow the rate law: rate = k[A]²[B].Predict by what factor the rate of reaction will increase when the concentration of A is doubled, the concentration of B is tripled, and the temperature remains constant.

The activation energy of a certain uncatalyzed reaction is 64 kJ/mol.In the presence of a catalyst, the E_a is 55 kJ/mol.How many times faster is the catalyzed than the uncatalyzed reaction at 400°C? Assume that the frequency factor remains the same.

A certain reaction, reaction A $\rarr$ products, is first order with respect to A.Starting with [A] = 0.250M, it takes 45 min to reduce the concentration of A to 0.110M.What is its rate constant for this reaction?

Which of the following elementary steps is bimolecular?

A reaction was experimentally determined to follow the rate law, Rate = k[A]² where k = 0.456 s^-1M^-1.Starting with [A]_o = 0.500 M, how many seconds will it take for [A]_t = 0.250 M?

The activation energy for the reaction CH₃CO $\rarr$ CH₃ + CO is 71 kJ/mol.How many times greater is the rate constant for this reaction at 170°C than at 150°C?

Chemistry: the Study of Change

Atoms, Molecules, and Ions

Mass Relationships in Chemical Reactions

Reactions in Aqueous Solutions

Gases

Thermochemistry

Quantum Theory and the Electronic Structure of Atoms

Periodic Relationships Among the Elements

Chemical Bonding I: Basic Concepts

Chemical Bonding Ii: Molecular Geometry and Hybridization of Atomic Orbitals

Intermolecular Forces and Liquids and Solids

Physical Properties of Solutions

Chemical Equilibrium

Acids and Bases

Acid-Base Equilibria and Solubility Equilibria

Entropy Free Energy and Equilibrium

Electrochemistry

Nuclear Chemistry

Chemistry in the Atmosphere

Metallurgy and the Chemistry of Metals

Nonmetallic Elements and Their Compounds

Transition Metal Chemistry and Coordination Compounds

Organic Chemistry

Synthetic and Natural Organic Polymers

Filters

Exam 13: Chemical Kinetics

In the reaction, 2N2O →\rarr→ 2N2 + O2, oxygen and nitrogen gases are formed at the same rate (mol/L·s).

For what order reaction does the half-life get longer as the initial concentration increases?

The rate constant of a first-order reaction, A →\rarr→ products, can be determined from a graph of ln[A] versus t.

For the chemical reaction A →\rarr→ B + C, a plot of [A]t versus time is found to give a straight line with a negative slope.What is the order of reaction with respect to A?

Nitrogen pentoxide decomposes by a first-order process yielding N2O4 and oxygen. 2N2O5 →\rarr→ 2N2O4 + O2 At a given temperature, the half-life of N2O5 is 0.90 hr.What is the first-order rate constant for N2O5 decomposition?

A certain reaction A →\rarr→ products is second order with respect to A with a rate constant, k, 0.122 M-1min-1.Starting with [A]o = 1.01M, how many seconds will it take for A to reach a concentration of 0.750M?

The reaction 2A + B →\rarr→ products is second order with respect to A and zero-order with respect to B.Starting with 0.135 M of A, what is the concentration of A after 35 min if the rate constant is 0.11 M-1s-1?

The activation energy for a certain reaction is 113 kJ/mol.By what factor (how many times)will the rate constant increase when the temperature is raised from 310 K to 325 K?

For the first-order reaction, A →\rarr→ products, if half of the initial concentration of A reacts in 20 min, then the remaining half will completely react in the next 20 min.

Nitric oxide gas (NO)reacts with chlorine gas according to the chemical equation given below. NO + Cl2 →\rarr→ NOCl The following initial rates of reaction have been measured for the given reagent concentrations. Which of the following is the rate law (rate equation)for this reaction?

The reaction A + 2B →\rarr→ products was found to follow the rate law: rate = k[A]2[B].Predict by what factor the rate of reaction will increase when the concentration of A is doubled, the concentration of B is tripled, and the temperature remains constant.

The activation energy of a certain uncatalyzed reaction is 64 kJ/mol.In the presence of a catalyst, the Ea is 55 kJ/mol.How many times faster is the catalyzed than the uncatalyzed reaction at 400°C? Assume that the frequency factor remains the same.

A certain reaction, reaction A →\rarr→ products, is first order with respect to A.Starting with [A] = 0.250M, it takes 45 min to reduce the concentration of A to 0.110M.What is its rate constant for this reaction?

At a certain temperature, the data below were collected for the reaction below. 2ICl + H2 →\rarr→ I2 + 2HCl. Determine the rate law for the reaction.

Which of the following elementary steps is bimolecular?

A reaction was experimentally determined to follow the rate law, Rate = k[A]2 where k = 0.456 s-1M-1.Starting with [A]o = 0.500 M, how many seconds will it take for [A]t = 0.250 M?

The activation energy for the reaction CH3CO →\rarr→ CH3 + CO is 71 kJ/mol.How many times greater is the rate constant for this reaction at 170°C than at 150°C?

Chemistry: the Study of Change

Atoms, Molecules, and Ions

Mass Relationships in Chemical Reactions

Reactions in Aqueous Solutions

Gases

Thermochemistry

Quantum Theory and the Electronic Structure of Atoms

Periodic Relationships Among the Elements

Chemical Bonding I: Basic Concepts

Chemical Bonding Ii: Molecular Geometry and Hybridization of Atomic Orbitals

Intermolecular Forces and Liquids and Solids

Physical Properties of Solutions

Chemical Equilibrium

Acids and Bases

Acid-Base Equilibria and Solubility Equilibria

Entropy Free Energy and Equilibrium

Electrochemistry

Nuclear Chemistry

Chemistry in the Atmosphere

Metallurgy and the Chemistry of Metals

Nonmetallic Elements and Their Compounds

Transition Metal Chemistry and Coordination Compounds

Organic Chemistry

Synthetic and Natural Organic Polymers

Filters

In the reaction, 2N₂O $\rarr$ 2N₂ + O₂, oxygen and nitrogen gases are formed at the same rate (mol/L·s).

The rate constant of a first-order reaction, A $\rarr$ products, can be determined from a graph of ln[A] versus t.

For the chemical reaction A $\rarr$ B + C, a plot of [A]_t versus time is found to give a straight line with a negative slope.What is the order of reaction with respect to A?

Nitrogen pentoxide decomposes by a first-order process yielding N₂O₄ and oxygen. 2N₂O₅ $\rarr$ 2N₂O₄ + O₂ At a given temperature, the half-life of N₂O₅ is 0.90 hr.What is the first-order rate constant for N₂O₅ decomposition?

A certain reaction A $\rarr$ products is second order with respect to A with a rate constant, k, 0.122 M^-1min^-1.Starting with [A]_o = 1.01M, how many seconds will it take for A to reach a concentration of 0.750M?

The reaction 2A + B $\rarr$ products is second order with respect to A and zero-order with respect to B.Starting with 0.135 M of A, what is the concentration of A after 35 min if the rate constant is 0.11 M^-1s^-1?

For the first-order reaction, A $\rarr$ products, if half of the initial concentration of A reacts in 20 min, then the remaining half will completely react in the next 20 min.

The reaction A + 2B $\rarr$ products was found to follow the rate law: rate = k[A]²[B].Predict by what factor the rate of reaction will increase when the concentration of A is doubled, the concentration of B is tripled, and the temperature remains constant.

The activation energy of a certain uncatalyzed reaction is 64 kJ/mol.In the presence of a catalyst, the E_a is 55 kJ/mol.How many times faster is the catalyzed than the uncatalyzed reaction at 400°C? Assume that the frequency factor remains the same.

A certain reaction, reaction A $\rarr$ products, is first order with respect to A.Starting with [A] = 0.250M, it takes 45 min to reduce the concentration of A to 0.110M.What is its rate constant for this reaction?

A reaction was experimentally determined to follow the rate law, Rate = k[A]² where k = 0.456 s^-1M^-1.Starting with [A]_o = 0.500 M, how many seconds will it take for [A]_t = 0.250 M?

The activation energy for the reaction CH₃CO $\rarr$ CH₃ + CO is 71 kJ/mol.How many times greater is the rate constant for this reaction at 170°C than at 150°C?