
(a)
Interpretation:
The rate law for the reaction should be determined by using concentration versus time.
Concept Introduction:
Rate Law can be expressed as an integrated rate law and a differential rate law.
Differential Rate Law: This describes the change in the concentrations of reactant as a function of time.
Integrated Rate Law: This describes the initial concentrations and the measured concentration of one or more reactants as a function of time.
(a)

Answer to Problem 136MP
Rate law for the reaction is:
Explanation of Solution
Given information:
Data is given as:
Time (s) | Experiment 1 | Experiment 2 |
0 | ||
10 | ||
20 | ||
30 | ? | |
40 |
In experiment 1, concentration of B is 10.0 M and in experiment 2, concentration of B is
20.0 M.
The order of reaction can be determined by the concentration and time data.
The general expression of rate law is expressed as:
Where, m and n are the experimentally determined values.
In both experiments, the concentration of B is more than the concentration of A, thus
In first experiment, 40 seconds are required to undergo one half-life of reactant A. In experiment 2, the half-life decreases by factor 4 as concentration of B doubles.
This observation implies that the reaction is second order with respect to B whereas the reaction is first order with respect to A as the
Thus, rate law for the reaction is expressed as:
(b)
Interpretation:
The value of rate constant including units should be calculated.
Concept Introduction:
Rate Law can be expressed as an integrated rate law and a differential rate law.
Differential Rate Law: This describes the change in the concentrations of reactant as a function of time.
Integrated Rate Law: This describes the initial concentrations and the measured concentration of one or more reactants as a function of time.
The proportionality coefficient which relates the rate of
(b)

Answer to Problem 136MP
Rate constant =
Explanation of Solution
Given information:
Data is given as:
Time (s) | Experiment 1 | Experiment 2 |
0 | ||
10 | ||
20 | ||
30 | ? | |
40 |
In experiment 1, concentration of B is 10.0 M and in experiment 2, concentration of B is
20.0 M.
In second experiment, the concentration decreases by half every ten seconds. As the reaction is first order with respect A, the below mathematical expression is used for determining value of rate of constant (k’).
Put the value of half-life,
Rate law for the given reaction is expressed as:
Since, concentration of B is more in comparison to A, thus, rate law is written as:
Where,
Put the values,
(c)
Interpretation:
The concentration of
Concept Introduction:
Rate Law can be expressed as an integrated rate law and a differential rate law.
Differential Rate Law: This describes the change in the concentrations of reactant as a function of time.
Integrated Rate Law: This describes the initial concentrations and the measured concentration of one or more reactants as a function of time.
The concentration of a reaction at any time is calculated by the values of concentration and time or by drawing the graph between concentration and time.
The rate constant expression for first order reaction is:
(c)

Answer to Problem 136MP
Concentration of A for first experiment at t = 30 s is
Explanation of Solution
Given information:
Data is given as:
Time (s) | Experiment 1 | Experiment 2 |
0 | ||
10 | ||
20 | ||
30 | ? | |
40 |
In experiment 1, concentration of B is 10.0 M and in experiment 2, concentration of B is
20.0 M.
Since, the reaction is first order with respect to A, thus, the rate constant expression is:
Where, k = rate constant
t = time
Co = Initial concentration
C = Concentration at given time.
Put the values from experiment 1,
Now, at t = 30 s
Put the values,
Thus, concentration of A for first experiment at t = 30 s is
(d)
Interpretation:
Among the given three mechanisms, the best mechanism for the given reaction should be determined. Also, reason should be explained for excluding any mechanism along with if all the three mechanism are equally good, reason should be explained.
Concept Introduction:
Rate Law can be expressed as an integrated rate law and a differential rate law.
Differential Rate Law: This describes the change in the concentrations of reactant as a function of time.
Integrated Rate Law: This describes the initial concentrations and the measured concentration of one or more reactants as a function of time.
(d)

Answer to Problem 136MP
The best mechanism is first mechanism.
Explanation of Solution
Given information:
The given reaction is:
For the given
Among the given mechanisms, first and third mechanisms give same rate law to the rate law of the given reaction. Thus, both first and third mechanism is possible. In case of second mechanism, rate law is not same to the rate law of given reaction.
Also, third mechanism is very rare to takes place. Thus, best mechanism is first mechanism.
Want to see more full solutions like this?
Chapter 15 Solutions
Chemical Principles
- Synthesize 2-Ethyl-3-methyloxirane from dimethyl(propyl)sulfonium iodide using the necessary organic or inorganic reagents. Draw the structures of the compounds.arrow_forwardSynthesize 2-Hydroxy-2-phenylacetonitrile from phenylmethanol using the necessary organic or inorganic reagents. Draw the structures of the compounds.arrow_forwardSynthesize N-Methylcyclohexylamine from cyclohexanol using the necessary organic or inorganic reagents. Draw the structures of the compounds.arrow_forward
- Synthesize N-Methylcyclohexylamine from cyclohexanol using the necessary organic or inorganic reagents. Draw the structures of the compounds.arrow_forwardIf possible, please provide the formula of the compound 3,3-dimethylbut-2-enal.arrow_forwardSynthesize 1,4-dibromobenzene from acetanilide (N-phenylacetamide) using the necessary organic or inorganic reagents. Draw the structures of the compounds.arrow_forward
- Indicate the products obtained by mixing (3-oxo-3-phenylpropyl)triphenylphosphonium bromide with sodium hydride.arrow_forwardWe mix N-ethyl-2-hexanamine with excess methyl iodide and followed by heating with aqueous Ag2O. Indicate the major products obtained.arrow_forwardIndicate the products obtained by mixing acetophenone with iodine and NaOH.arrow_forward
- Indicate the products obtained by mixing 2-Propanone and ethyllithium and performing a subsequent acid hydrolysis.arrow_forwardIndicate the products obtained if (E)-2-butenal and 3-oxo-butanenitrile are mixed with sodium ethoxide in ethanol.arrow_forwardQuestion 3 (4 points), Draw a full arrow-pushing mechanism for the following reaction Please draw all structures clearly. Note that this intramolecular cyclization is analogous to the mechanism for halohydrin formation. COH Br + HBr Brarrow_forward
- ChemistryChemistryISBN:9781305957404Author:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCostePublisher:Cengage LearningChemistry: An Atoms First ApproachChemistryISBN:9781305079243Author:Steven S. Zumdahl, Susan A. ZumdahlPublisher:Cengage Learning
- Chemistry: The Molecular ScienceChemistryISBN:9781285199047Author:John W. Moore, Conrad L. StanitskiPublisher:Cengage LearningChemistry & Chemical ReactivityChemistryISBN:9781337399074Author:John C. Kotz, Paul M. Treichel, John Townsend, David TreichelPublisher:Cengage LearningChemistry & Chemical ReactivityChemistryISBN:9781133949640Author:John C. Kotz, Paul M. Treichel, John Townsend, David TreichelPublisher:Cengage Learning





