Tetrafluoroethylene, C2F4, can be converted to octafluorocyclobutane which can be used as a refrigerant or an aerosol propellant. A plot of 1/[C2F4] vs. time gives a straight line with a slope of 0.0448 L mol¯1s¯1. What is the rate law for this reaction?

A) Rate = 0.0448 (L mol¯1s¯1)[C2F4] B) Rate = 22.3 (mol L¯1s)[C2F4] C) Rate = 0.0448 (L mol¯1s¯1)[C2F4]2 D) Rate = 22.3 (mol L¯1s)[C2F4]2 E) Rate = 0.0448 s¯1 [C2F4] A) Rate = 0.0448 (L mol¯1s¯1)[C2F4] B) Rate = 22.3 (mol L¯1s)[C2F4] C) Rate = 0.0448 (L mol¯1s¯1)[C2F4]2 D) Rate = 22.3 (mol L¯1s)[C2F4]2 E) Rate = 0.0448 s¯1 [C2F4]

The rate law for the rearrangement of CH3NC to CH3CN at 800 K is Rate = (1300 s¯1)[CH3NC]. What is the half-life for this reaction?

A) 7.69 * 10¯4 s B) 5.3* 10¯4 s C) 1.9 * 10¯3 s D) 520 s E) 1920 s A) 7.69 * 10¯4 s B) 5.3* 10¯4 s C) 1.9 * 10¯3 s D) 520 s E) 1920 s

The rate law for the reaction 3A $\rightarrow$ C is Rate = 4.36 *10¯2 L mol¯1 hr¯1[A]2 What is the half-life for the reaction if the initial concentration of A is 0.250 M?

A) 0.0109 hr B) 0.0629 hr C) 15.9 hr D) 23.9 hr E) 91.7 hr A) 0.0109 hr B) 0.0629 hr C) 15.9 hr D) 23.9 hr E) 91.7 hr

Dinitrogen tetraoxide, N2O4, decomposes to nitrogen dioxide, NO2, in a first-order process. If k = 2.5 * 103 s¯1 at -5$\degree$C and k = 3.5 * 104 s¯1 at 25$\degree$C, what is the activation energy for the decomposition?

A) 0.73 kJ/mol B) 58 kJ/mol C) 140 kJ/mol D) 580 kJ/mol E) > 1000 kJ/mol A) 0.73 kJ/mol B) 58 kJ/mol C) 140 kJ/mol D) 580 kJ/mol E) > 1000 kJ/mol

(p. Various sections) The gas-phase reaction has been studied in a closed vessel, and the rate equation was found to be: Rate = -$\Delta$[CH3NC]/$\Delta$t = k[CH3NC]. Which one of the following actions is least likely to cause a change in the rate of the reaction?

A) lowering the temperature B) adding a catalyst C) using a larger initial amount of CH3NC in the same vessel D) using a bigger vessel, but the same initial amount of CH3NC E) continuously removing CH3CN as it is formed A) lowering the temperature B) adding a catalyst C) using a larger initial amount of CH3NC in the same vessel D) using a bigger vessel, but the same initial amount of CH3NC E) continuously removing CH3CN as it is formed

A first-order reaction has a half-life of 20.0 minutes. Starting with 1.00 *1020 molecules of reactant at time t = 0, how many molecules remain unreacted after 100.0 minutes?

A) 1.00 * 104 molecules B) 2.00 * 1019 molecules C) 3.20 *1016 molecules D) 5.00 * 1020 molecules E) None of these choices is correct. A) 1.00 * 104 molecules B) 2.00 * 1019 molecules C) 3.20 *1016 molecules D) 5.00 * 1020 molecules E) None of these choices is correct.

The radioactive isotope tritium decays with a first-order rate constant k of 0.056 year¯1. What fraction of the tritium initially in a sample is still present 30 years later?

A) 0.19 B) 0.60 C) 0.15 D) 2.8 *10¯38 E) None of these choices is correct. A) 0.19 B) 0.60 C) 0.15 D) 2.8 *10¯38 E) None of these choices is correct.

Exam 16: Kinetics: Rates and Mechanisms of Chemical Reactions

Tetrafluoroethylene, C₂F₄, can be converted to octafluorocyclobutane which can be used as a refrigerant or an aerosol propellant. A plot of 1/[C₂F₄] vs. time gives a straight line with a slope of 0.0448 L mol¯¹s¯¹. What is the rate law for this reaction?

(Multiple Choice)

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Question 21

According to the collision theory of reaction rates, what are the three requirements which must be met before an elementary reaction between two molecules can occur?

(Essay)

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Question 22

Consider the following mechanism for the oxidation of bromide ions by hydrogen peroxide in aqueous acid solution. Which of the following rate laws is consistent with the mechanism?

(Multiple Choice)

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Question 23

If the activation energy of a reaction decreases by 10.0 kJ/mol, from 100.0 to 90.0 kJ/mol, what effect will this have on the rate of reaction at 298K?

(Multiple Choice)

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Question 24

The rate law for the rearrangement of CH₃NC to CH₃CN at 800 K is Rate = (1300 s¯¹)[CH₃NC]. What is the half-life for this reaction?

(Multiple Choice)

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Question 25

The rate law for the reaction 3A $\rightarrow$ C is Rate = 4.36 *10¯² L mol¯¹ hr¯¹[A]² What is the half-life for the reaction if the initial concentration of A is 0.250 M?

(Multiple Choice)

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Question 26

Briefly outline the key arguments in the collision theory of reaction rates for the elementary reaction products. Show that this theory predicts a second-order rate law, and how it predicts the form of the rate constant k.

(Essay)

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Question 27

Dinitrogen tetraoxide, N₂O₄, decomposes to nitrogen dioxide, NO₂, in a first-order process. If k = 2.5 * 10³ s¯¹ at -5 $\degree$ C and k = 3.5 * 10⁴ s¯¹ at 25 $\degree$ C, what is the activation energy for the decomposition?

(Multiple Choice)

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Question 28

A transition state is a species (or state) corresponding to an energy maximum on a reaction energy diagram.

(True/False)

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Question 29

Is a bimolecular reaction necessarily second-order? Is a second-order reaction necessarily bimolecular? Answer, with explanations and clarifications.

(Essay)

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Question 30

The compound RX₃ decomposes according to the equation 3RX₃ $\rightarrow$ R + R₂X₃ + 3X₂In an experiment the following data were collected for the decomposition at 100 $\degree$ C. What is the average rate of reaction over the entire experiment? $The compound RX3 decomposes according to the equation 3RX3 \rightarrow R + R2X3 + 3X2 In an experiment the following data were collected for the decomposition at 100 \degree C. What is the average rate of reaction over the entire experiment?$

(Multiple Choice)

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Question 31

A reaction has the following rate law: Rate = k[A][B]² In experiment 1, the concentrations of A and B are both 0.10 mol L^¯1; in experiment 2, the concentrations are both 0.30 mol L^¯1. If the temperature stays constant, what is the value of the ratio, Rate(2)/Rate(1)?

(Multiple Choice)

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Question 32

(p. Various sections) The gas-phase reaction $(p. Various sections) The gas-phase reaction has been studied in a closed vessel, and the rate equation was found to be: Rate = - \Delta [CH3NC]/ \Delta t = k[CH3NC]. Which one of the following actions is least likely to cause a change in the rate of the reaction?$ has been studied in a closed vessel, and the rate equation was found to be: Rate = - $\Delta$ [CH₃NC]/ $\Delta$ t = k[CH₃NC]. Which one of the following actions is least likely to cause a change in the rate of the reaction?

(Multiple Choice)

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Question 33

A first-order reaction has a half-life of 20.0 minutes. Starting with 1.00 *10²⁰ molecules of reactant at time t = 0, how many molecules remain unreacted after 100.0 minutes?

(Multiple Choice)

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Question 34

An elementary reaction is a simple, one-step process.

(True/False)

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Question 35

In an exothermic reaction,

(Multiple Choice)

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Question 36

For the reaction 2A + B + 2C $\rightarrow$ D + E, the following initial rate data were collected at constant temperature. Determine the correct rate law for this reaction. All units are arbitrary. $For the reaction 2A + B + 2C \rightarrow D + E, the following initial rate data were collected at constant temperature. Determine the correct rate law for this reaction. All units are arbitrary.$

(Multiple Choice)

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Question 37

A reaction is first-order with respect to the reactant R. Which of the following plots will produce a straight line?

(Multiple Choice)

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Question 38

For each of the following terms/concepts, give a brief explanation or definition. Where possible, use examples. A) order of a reaction B) elementary reaction C) reaction intermediate

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Question 39

The radioactive isotope tritium decays with a first-order rate constant k of 0.056 year¯¹. What fraction of the tritium initially in a sample is still present 30 years later?

(Multiple Choice)

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Question 40

Showing 21 - 40 of 89

Exam 16: Kinetics: Rates and Mechanisms of Chemical Reactions

Tetrafluoroethylene, C2F4, can be converted to octafluorocyclobutane which can be used as a refrigerant or an aerosol propellant. A plot of 1/[C2F4] vs. time gives a straight line with a slope of 0.0448 L mol¯1s¯1. What is the rate law for this reaction?

According to the collision theory of reaction rates, what are the three requirements which must be met before an elementary reaction between two molecules can occur?

Consider the following mechanism for the oxidation of bromide ions by hydrogen peroxide in aqueous acid solution. Which of the following rate laws is consistent with the mechanism?

If the activation energy of a reaction decreases by 10.0 kJ/mol, from 100.0 to 90.0 kJ/mol, what effect will this have on the rate of reaction at 298K?

The rate law for the rearrangement of CH3NC to CH3CN at 800 K is Rate = (1300 s¯1)[CH3NC]. What is the half-life for this reaction?

The rate law for the reaction 3A →\rightarrow→ C is Rate = 4.36 *10¯2 L mol¯1 hr¯1[A]2 What is the half-life for the reaction if the initial concentration of A is 0.250 M?

Briefly outline the key arguments in the collision theory of reaction rates for the elementary reaction products. Show that this theory predicts a second-order rate law, and how it predicts the form of the rate constant k.

Dinitrogen tetraoxide, N2O4, decomposes to nitrogen dioxide, NO2, in a first-order process. If k = 2.5 * 103 s¯1 at -5 °\degree° C and k = 3.5 * 104 s¯1 at 25 °\degree° C, what is the activation energy for the decomposition?

A transition state is a species (or state) corresponding to an energy maximum on a reaction energy diagram.

Is a bimolecular reaction necessarily second-order? Is a second-order reaction necessarily bimolecular? Answer, with explanations and clarifications.

The compound RX3 decomposes according to the equation 3RX3 →\rightarrow→ R + R2X3 + 3X2 In an experiment the following data were collected for the decomposition at 100 °\degree° C. What is the average rate of reaction over the entire experiment?

A reaction has the following rate law: Rate = k[A][B]2 In experiment 1, the concentrations of A and B are both 0.10 mol L¯1; in experiment 2, the concentrations are both 0.30 mol L¯1. If the temperature stays constant, what is the value of the ratio, Rate(2)/Rate(1)?

(p. Various sections) The gas-phase reaction has been studied in a closed vessel, and the rate equation was found to be: Rate = - Δ\DeltaΔ [CH3NC]/ Δ\DeltaΔ t = k[CH3NC]. Which one of the following actions is least likely to cause a change in the rate of the reaction?

A first-order reaction has a half-life of 20.0 minutes. Starting with 1.00 *1020 molecules of reactant at time t = 0, how many molecules remain unreacted after 100.0 minutes?

An elementary reaction is a simple, one-step process.

In an exothermic reaction,

For the reaction 2A + B + 2C →\rightarrow→ D + E, the following initial rate data were collected at constant temperature. Determine the correct rate law for this reaction. All units are arbitrary.

A reaction is first-order with respect to the reactant R. Which of the following plots will produce a straight line?

For each of the following terms/concepts, give a brief explanation or definition. Where possible, use examples. A) order of a reaction B) elementary reaction C) reaction intermediate

The radioactive isotope tritium decays with a first-order rate constant k of 0.056 year¯1. What fraction of the tritium initially in a sample is still present 30 years later?

Keys to the Study of Chemistry

The Components of Matter

Stoichiometry of Formulas and Equations

Three Major Classes of Chemical Reactions

Gases and the Kinetic-Molecular Theory

Thermochemistry: Energy Flow and Chemical Change

Quantum Theory and Atomic Structure

Electron Configuration and Chemical Periodicity

Models of Chemical Bonding

The Shapes of Molecules

Theories of Covalent Bonding

Intermolecular Forces: Liquids, Solids, and Phase Changes

The Properties of Mixtures: Solutions and Colloids

Periodic Patterns in the Main-Group Elements

Organic Compounds and the Atomic Properties of Carbon

Equilibrium: the Extent of Chemical Reactions

Acid-Base Equilibria

Ionic Equilibria in Aqueous Systems

Thermodynamics: Entropy, Free Energy, and the Direction of Chemical Reactions

Electrochemistry: Chemical Change and Electrical Work

The Elements in Nature and Industry

The Transition Elements and Their Coordination Compounds

Nuclear Reactions and Their Applications

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Tetrafluoroethylene, C₂F₄, can be converted to octafluorocyclobutane which can be used as a refrigerant or an aerosol propellant. A plot of 1/[C₂F₄] vs. time gives a straight line with a slope of 0.0448 L mol¯¹s¯¹. What is the rate law for this reaction?

The rate law for the rearrangement of CH₃NC to CH₃CN at 800 K is Rate = (1300 s¯¹)[CH₃NC]. What is the half-life for this reaction?

The rate law for the reaction 3A $\rightarrow$ C is Rate = 4.36 *10¯² L mol¯¹ hr¯¹[A]² What is the half-life for the reaction if the initial concentration of A is 0.250 M?

Dinitrogen tetraoxide, N₂O₄, decomposes to nitrogen dioxide, NO₂, in a first-order process. If k = 2.5 * 10³ s¯¹ at -5 $\degree$ C and k = 3.5 * 10⁴ s¯¹ at 25 $\degree$ C, what is the activation energy for the decomposition?

A reaction has the following rate law: Rate = k[A][B]² In experiment 1, the concentrations of A and B are both 0.10 mol L^¯1; in experiment 2, the concentrations are both 0.30 mol L^¯1. If the temperature stays constant, what is the value of the ratio, Rate(2)/Rate(1)?

A first-order reaction has a half-life of 20.0 minutes. Starting with 1.00 *10²⁰ molecules of reactant at time t = 0, how many molecules remain unreacted after 100.0 minutes?

The radioactive isotope tritium decays with a first-order rate constant k of 0.056 year¯¹. What fraction of the tritium initially in a sample is still present 30 years later?