McMurry - Chemistry 8th Edition

Ch.14 - Chemical Kinetics

Back

All textbooks

McMurry 8th Edition

Ch.14 - Chemical Kinetics

Problem 66
Initial rate data at 25 °C are listed in the table for the reaction NH4 +1aq2 + NO2 -1aq2S N21g2 + 2 H2O1l2 (b) What is the value of the rate constant?
Problem 69
Trimethylamine and chlorine dioxide react in water in an electron transfer reaction to form the trimethylamine cation and chlorite ion: 1CH323 N1aq2 + ClO21aq2 + H2O1l2S 1CH323 NH+1aq2 + ClO2 -1aq2 + OH-1aq2 Initial rate data obtained at 23 °C are listed in the following table. (b) What would be the initial rate in an experiment with initial concentrations 31CH323 N4 = 4.2 * 10-2 M and 3ClO24 = 3.4 * 10-2 M?
Problem 74
Butadiene C4H6 reacts with itself to form a dimer with the formula C8H12. The reaction is second order in C4H6. Assume the rate constant at a particular temperature is 4.0 × 10^-2 M^-1 s^-1 and the initial concentration of C4H6 is 0.0200 M. (a) What is its molarity after a reaction time of 1.00 h?
Problem 75
Hydrogen iodide decomposes slowly to H2 and I2 at 600 K. The reaction is second order in HI, and the rate constant is 9.7 * 10^-6 M^-1 s^-1. Assume the initial concentration of HI is 0.100 M. (a) What is its molarity after a reaction time of 6.00 days?
Problem 76
What is the half-life (in minutes) of the reaction in Problem 14.74 when the initial C4H6 concentration is 0.0200 M? How many minutes does it take for the concentration of C4H6 to drop from 0.0100 M to 0.0050 M?
Problem 79
The decomposition of N2O5 is a first-order reaction. At 25 °C, it takes 5.2 h for the concentration to drop from 0.120 M to 0.060 M. How many hours does it take for the concentration to drop from 0.030 M to 0.015 M? From 0.480 M to 0.015 M?
Problem 80
You wish to determine the reaction order and rate constant for the following thermal decomposition reaction: AB2 S 1>2 A2 + B2 (c) Describe how you would determine the value of the rate constant.
Problem 82
Nitrosyl bromide decomposes at 10 °C. NOBr1g2S NO1g2 + 1>2 Br21g2 Use the following kinetic data to determine the order of the reaction and the value of the rate constant for consumption of NOBr.

Problem 83

Consider the following concentration–time data for the decomposition reaction AB → A + B. (c) What is the time (in minutes) when the AB concentration reaches a value of 0.0250 M?

Problem 83a

Consider the following concentration–time data for the decomposition reaction AB → A + B.

(a) Determine the order of the reaction and the value of the rate constant.

Problem 83b

Consider the following concentration–time data for the decomposition reaction AB → A + B.

(b) What is the molarity of AB after a reaction time of 192 min?

Problem 92b

Consider three reactions with different values of E_a and ΔE:

Reaction 1. E_a = 20 kJ>mol; ΔE = -60 kJ/mol

Reaction 2. E_a = 10 kJ>mol; ΔE = -20 kJ/mol

Reaction 3. E_a = 40 kJ>mol; ΔE = +15 kJ/mol

(b) Assuming that all three reactions are carried out at the same temperature and that all three have the same frequency factor A, which reaction is the fastest and which is the slowest?

Problem 92c

Consider three reactions with different values of E_a and ΔE:

Reaction 1. E_a = 20 kJ>mol; ΔE = -60 kJ/mol

Reaction 2. E_a = 10 kJ>mol; ΔE = -20 kJ/mol

Reaction 3. E_a = 40 kJ>mol; ΔE = +15 kJ/mol

Problem 95

A certain first-order reaction has a rate constant of 1.0 * 10-3 s-1 at 25 °C. (b) What is the Ea (in kJ/mol) if the same temperature change causes the rate to triple?

Problem 98

If the rate of a reaction increases by a factor of 2.5 when the temperature is raised from 20 °C to 30 °C, what is the value of the activation energy in kJ/mol? By what factor does the rate of this reaction increase when the temperature is raised from 120 °C to 130 °C?

Problem 100

You wish to determine the activation energy for the following first-order reaction: AS B + C (b) How would you use these data to determine the activation energy?

Problem 104

What is the relationship between the coefficients in a balanced chemical equation for an overall reaction and the exponents in the rate law?

Problem 105

What distinguishes the rate-determining step from the other steps in a reaction mechanism? How does the ratedetermining step affect the observed rate law?

Problem 106

Consider the following mechanism for the reaction of hydrogen and iodine monochloride: Step 1. H21g2 + ICl1g2S HI1g2 + HCl1g2 Step 2. HI1g2 + ICl1g2S I21g2 + HCl1g2 (b) Identify any reaction intermediates.

Problem 110

The thermal decomposition of nitryl chloride, NO2Cl, is believed to occur by the following mechanism: NO2Cl1g2 ¡ k1 NO21g2 + Cl1g2 Cl1g2 + NO2Cl1g2 ¡ k2 NO21g2 + Cl21g2 (c) What rate law is predicted by this mechanism if the first step is rate-determining?

Problem 114a

A proposed mechanism for the oxidation of nitric oxide to nitrogen dioxide was described in Problem 14.29. Another possible mechanism for this reaction is

(a) Write a balanced equation for the overall reaction.

Problem 114b

A proposed mechanism for the oxidation of nitric oxide to nitrogen dioxide was described in Problem 14.29. Another possible mechanism for this reaction is

(b) Show that this mechanism is consistent with the experimental rate law, Rate = k[NO₄][O₂].

Problem 114c

A proposed mechanism for the oxidation of nitric oxide to nitrogen dioxide was described in Problem 14.29. Another possible mechanism for this reaction is

Problem 116

Comment on the following statement: 'A catalyst increases the rate of a reaction, but it is not consumed because it does not participate in the reaction.'

Problem 66

Problem 69

Problem 74

Problem 75

Problem 76

Problem 79

Problem 80

Problem 82

Problem 83

Problem 83a

Problem 83b

Problem 84

Problem 86

Problem 87

Problem 88

Problem 89

Problem 91

Problem 92b

Problem 92c

Problem 95

Problem 98

Problem 100

Problem 104

Problem 105

Problem 106

Problem 110

Problem 114a

Problem 114b

Problem 114c

Problem 116