Question 1

The instantaneous rate of a reaction can be read directly from the graph of molarity versus time at any point on the graph.

Accepted Answer

A) True 
 B)False

Question 2

The reaction 2NOBr (g)→ 2 NO (g)+ Br2 (g)
Is a second-order reaction with a rate constant of 0.80 M-1s-1 at 11°C. If the initial concentration of NOBr is 0.0440 M, the concentration of NOBr after 7.0 seconds is __________.

Accepted Answer

A) 0.0276 M 
B) 0.0324 M 
C) 0.0353 M 
D) 0.0480 M 
E) 0.0402 M 
A) 0.0276 M 
B) 0.0324 M 
C) 0.0353 M 
D) 0.0480 M 
E) 0.0402 M

Question 3

Heterogeneous catalysts have different phases from reactants.

Accepted Answer

A) True 
 B)False

Question 4

In general, as temperature goes down, reaction rate __________.

Accepted Answer

A) goes down if the reaction is exothermic 
B) goes down if the reaction is endothermic 
C) stays the same regardless of whether the reaction is exothermic or endothermic 
D) goes down regardless of whether the reaction is exothermic or endothermic 
E) none of the above 
A) goes down if the reaction is exothermic 
B) goes down if the reaction is endothermic 
C) stays the same regardless of whether the reaction is exothermic or endothermic 
D) goes down regardless of whether the reaction is exothermic or endothermic 
E) none of the above

Question 5

For the elementary reaction NO3 + CO → NO2 + CO2
The molecularity of the reaction is __________, and the rate law is rate = __________.

Accepted Answer

A) 2, k[NO3][CO] 
B) 4, k[NO3][CO][NO2][CO2] 
C) 2, k[NO2][CO2] 
D) 2, k[NO3][CO]/[NO2][CO2] 
E) 4, k[NO2][CO2]/[NO3][CO] 
A) 2, k[NO3][CO] 
B) 4, k[NO3][CO][NO2][CO2] 
C) 2, k[NO2][CO2] 
D) 2, k[NO3][CO]/[NO2][CO2] 
E) 4, k[NO2][CO2]/[NO3][CO]

Question 6

The initial concentration of reactant in a first-order reaction is 0.27 M. The rate constant for the reaction is 0.75 s-1. What is the concentration (mol/L)of reactant after 0.50 s?

Accepted Answer

A) 0.64 
B) 1.7 
C) 0.19 
D) 0.11 
E) 0.39 
A) 0.64 
B) 1.7 
C) 0.19 
D) 0.11 
E) 0.39

Question 7

Of the units below, __________ are appropriate for a first-order reaction rate constant.

Accepted Answer

A) M s-1 
B) s-1 
C) mol/L 
D) M-1 s-1 
E) L mol-1 s-1 
A) M s-1 
B) s-1 
C) mol/L 
D) M-1 s-1 
E) L mol-1 s-1

Question 8

In general, as temperature goes up, reaction rate __________.

Accepted Answer

A) goes up if the reaction is exothermic 
B) goes up if the reaction is endothermic 
C) goes up regardless of whether the reaction is exothermic or endothermic 
D) stays the same regardless of whether the reaction is exothermic or endothermic 
E) stays the same if the reaction is first order 
A) goes up if the reaction is exothermic 
B) goes up if the reaction is endothermic 
C) goes up regardless of whether the reaction is exothermic or endothermic 
D) stays the same regardless of whether the reaction is exothermic or endothermic 
E) stays the same if the reaction is first order

Question 9

A compound decomposes by a first-order process. If 25.0% of the compound decomposes in 60.0 minutes, the half-life of the compound is __________.

Accepted Answer

A) 65 minutes 
B) 120 minutes 
C) 145 minutes 
D) 180 minutes 
E) 198 minutes 
A) 65 minutes 
B) 120 minutes 
C) 145 minutes 
D) 180 minutes 
E) 198 minutes

Question 10

The concentration of S2O82- remaining at 800 s is __________ M.

Accepted Answer

A) 0.046 
B) 0.076 
C) 4.00 × 10-3 
D) 0.015 
E) 0.041 
A) 0.046 
B) 0.076 
C) 4.00 × 10-3 
D) 0.015 
E) 0.041

Question 11

The rate of a second order reaction can depend on the concentrations of more than one reactant.

Accepted Answer

A) True 
 B)False

Question 12

The rate constant for this reaction is __________ s-1.

Accepted Answer

A) 6.9 × 10-2 
B) 3.0 × 10-2 
C) 14 
D) 0.46 
E) 4.0 × 102 
A) 6.9 × 10-2 
B) 3.0 × 10-2 
C) 14 
D) 0.46 
E) 4.0 × 102

Question 13

The concentration of A is __________ M after 40.0 s.

Accepted Answer

A) 1.3 × 10-2 
B) 1.2 
C) 0.17 
D) 3.5 × 10-4 
E) 0.025 
A) 1.3 × 10-2 
B) 1.2 
C) 0.17 
D) 3.5 × 10-4 
E) 0.025

Question 14

A first-order reaction has a rate constant of 0.33 min-1. It takes __________ min for the reactant concentration to decrease from 0.13 M to 0.095 M.

Accepted Answer

A) 0.085 
B) 0.13 
C) 0.41 
D) 1.2 
E) 0.95 
A) 0.085 
B) 0.13 
C) 0.41 
D) 1.2 
E) 0.95

Question 15

The overall order of a reaction is 1. The units of the rate constant for the reaction are __________.

Accepted Answer

A) M/s 
B) M-1s-1 
C) 1/s 
D) 1/M 
E) s/M2 
A) M/s 
B) M-1s-1 
C) 1/s 
D) 1/M 
E) s/M2

Question 16

The uptake of molecules into the interior of another substance is referred to as __________.

Accepted Answer

The answer of The uptake of molecules into the interior...

Question 17

At elevated temperatures, dinitrogen pentoxide decomposes to nitrogen dioxide and oxygen: 2N2O5(g)→ 4NO2 (g)+ O2 (g)
When the rate of formation of NO2 is 5.5 × 10-4 M/s, the rate of decomposition of N2O5 is ________ M/s.

Accepted Answer

A) 2.2 × 10-3 
B) 1.4 × 10-4 
C) 10.1 × 10-4 
D) 2.8 × 10-4 
E) 5.5 × 10-4 
A) 2.2 × 10-3 
B) 1.4 × 10-4 
C) 10.1 × 10-4 
D) 2.8 × 10-4 
E) 5.5 × 10-4

Question 18

For the reaction aA + Bb → cC + dD the rate law is __________.

Accepted Answer

The answer of For the reaction aA + Bb →...

Question 19

The half-life of a first-order reaction is 13 min. If the initial concentration of reactant is 0.085 M, it takes __________ min for it to decrease to 0.055 M.

Accepted Answer

A) 8.2 
B) 11 
C) 3.6 
D) 0.048 
E) 8.4 
A) 8.2 
B) 11 
C) 3.6 
D) 0.048 
E) 8.4

Question 20

At elevated temperatures, dinitrogen pentoxide decomposes to nitrogen dioxide and oxygen: 2N2O5(g)→ 4NO2 (g)+ O2 (g)
When the rate of formation of O2 is 2.2 × 10-4 M/s, the rate of decomposition of N2O5 is __________ M/s.

Accepted Answer

A) 1.1 × 10-4 
B) 2.2 × 10-4 
C) 2.8 × 10-4 
D) 4.4 × 10-4 
E) 5.5 × 10-4 
A) 1.1 × 10-4 
B) 2.2 × 10-4 
C) 2.8 × 10-4 
D) 4.4 × 10-4 
E) 5.5 × 10-4

Exam 14: Chemical Kinetics

The instantaneous rate of a reaction can be read directly from the graph of molarity versus time at any point on the graph.

The reaction 2NOBr (g)→ 2 NO (g)+ Br2 (g) Is a second-order reaction with a rate constant of 0.80 M-1s-1 at 11°C. If the initial concentration of NOBr is 0.0440 M, the concentration of NOBr after 7.0 seconds is __________.

Heterogeneous catalysts have different phases from reactants.

In general, as temperature goes down, reaction rate __________.

For the elementary reaction NO3 + CO → NO2 + CO2 The molecularity of the reaction is __________, and the rate law is rate = __________.

The initial concentration of reactant in a first-order reaction is 0.27 M. The rate constant for the reaction is 0.75 s-1. What is the concentration (mol/L)of reactant after 0.50 s?

Of the units below, __________ are appropriate for a first-order reaction rate constant.

In general, as temperature goes up, reaction rate __________.

A compound decomposes by a first-order process. If 25.0% of the compound decomposes in 60.0 minutes, the half-life of the compound is __________.

The concentration of S2O82- remaining at 800 s is __________ M.

The rate of a second order reaction can depend on the concentrations of more than one reactant.

The rate constant for this reaction is __________ s-1.

The concentration of A is __________ M after 40.0 s.

A first-order reaction has a rate constant of 0.33 min-1. It takes __________ min for the reactant concentration to decrease from 0.13 M to 0.095 M.

The overall order of a reaction is 1. The units of the rate constant for the reaction are __________.

The uptake of molecules into the interior of another substance is referred to as __________.

At elevated temperatures, dinitrogen pentoxide decomposes to nitrogen dioxide and oxygen: 2N2O5(g)→ 4NO2 (g)+ O2 (g) When the rate of formation of NO2 is 5.5 × 10-4 M/s, the rate of decomposition of N2O5 is ________ M/s.

For the reaction aA + Bb → cC + dD the rate law is __________.

The half-life of a first-order reaction is 13 min. If the initial concentration of reactant is 0.085 M, it takes __________ min for it to decrease to 0.055 M.

At elevated temperatures, dinitrogen pentoxide decomposes to nitrogen dioxide and oxygen: 2N2O5(g)→ 4NO2 (g)+ O2 (g) When the rate of formation of O2 is 2.2 × 10-4 M/s, the rate of decomposition of N2O5 is __________ M/s.

Introduction: Matter and Measurement

Atoms, Molecules, and Ions

Stoichiometry: Calculations With Chemical Formulas and Equations

Aqueous Reactions and Solution Stoichiometry

Thermochemistry

Electronic Structure of Atoms

Periodic Properties of the Elements

Basic Concepts of Chemical Bonding

Molecular Geometry and Bonding Theories

Gases

Liquids and Intermolecular Forces

Solids and Modern Materials

Properties of Solutions

Chemical Equilibrium

Acid-Base Equilibria

Additional Aspects of Aqueous Equilibria

Chemistry of the Environment

Chemical Thermodynamics

Electrochemistry

Nuclear Chemistry

Chemistry of the Nonmetals

Transition Metals and Coordination Chemistry

The Chemistry of Life: Organic and Biological Chemistry

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The reaction 2NOBr (g)→ 2 NO (g)+ Br₂ (g) Is a second-order reaction with a rate constant of 0.80 M^-1s^-1at 11°C. If the initial concentration of NOBr is 0.0440 M, the concentration of NOBr after 7.0 seconds is __________.

For the elementary reaction NO₃ + CO → NO₂ + CO₂ The molecularity of the reaction is , and the rate law is rate = .

The initial concentration of reactant in a first-order reaction is 0.27 M. The rate constant for the reaction is 0.75 s^-1. What is the concentration (mol/L)of reactant after 0.50 s?

The concentration of S₂O₈^2- remaining at 800 s is __________ M.

The rate constant for this reaction is __________ s^-1.

A first-order reaction has a rate constant of 0.33 ^min-1. It takes __________ min for the reactant concentration to decrease from 0.13 M to 0.095 M.

At elevated temperatures, dinitrogen pentoxide decomposes to nitrogen dioxide and oxygen: 2N₂O₅(g)→ 4NO₂(g)+ O₂ (g) When the rate of formation of NO₂ is 5.5 × 10^-4 M/s, the rate of decomposition of N₂O₅ is ________ M/s.

At elevated temperatures, dinitrogen pentoxide decomposes to nitrogen dioxide and oxygen: 2N₂O₅(g)→ 4NO₂(g)+ O₂ (g) When the rate of formation of O₂ is 2.2 × 10^-4 M/s, the rate of decomposition of N₂O₅ is __________ M/s.