(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 117

Why doesn't a catalyst appear in the overall chemical equation for a reaction?

Problem 118

What distinguishes a catalyst from an intermediate?

Problem 122

The rate of the reaction A + B2 S AB + B is directly proportional to the concentration of B2, independent of the concentration of A, and directly proportional to the concentration of a substance C. (c) What is the role of C in this reaction? Why doesn't C appear in the chemical equation for the overall reaction?

Problem 123

The half-life of a typical peptide bond (the C–N bond in a protein backbone) in neutral aqueous solution is about 500 years. When a protease enzyme acts on a peptide bond, the bond’s half-life is about 0.010 s. Assuming that these half-lives correspond to first-order reactions, by what factor does the enzyme increase the rate of the peptide bond breaking reaction?

Problem 124

Consider the reaction H₂(g) + I₂(g) ⇌ 2 HI(g). The reaction of a fixed amount of H₂ and I₂ is studied in a cylinder fitted with a movable piston. Indicate the effect of each of the following changes on the rate of the reaction. (b) An increase in volume at constant temperature

Problem 124b

Consider the reaction H₂(g) + I₂(g) → 2 HI(g). The reaction of a fixed amount of H₂ and I₂ is studied in a cylinder fitted with a movable piston. Indicate the effect of each of the following changes on the rate of the reaction. (b) An increase in volume at constant temperature

Problem 124c

Problem 125

Concentration–time data for the conversion of A and B to D are listed in the following table.

Problem 80

Problem 82

Problem 83

Problem 83a

Problem 83b

Problem 84

Problem 86

Problem 87

Problem 89

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

Problem 117

Problem 118

Problem 122

Problem 123

Problem 124

Problem 124b

Problem 124c

Problem 125