Homework Help is Here – Start Your Trial Now!
Science
Chemistry
Information about the mechanism of the reaction undergone by a series of substituted benzenes can be obtained by plotting the logarithm of the observed rate constant determined at a particular pH against the Hammett substituent constant (o) for the particular substituent. The o value for hydrogen is 0. Electron-donating substituents have negative o values; the more strongly electron donating the substituent, the more negative its o value. Electron-withdrawing substituents have positive o values; the more strongly electron withdrawing the substituent, the more positive its o value. The slope of a plot of the logarithm of the rate constant versus o is called the p (rho) value. The p value for the hydroxide-ion-promoted hydrolysis of a series of meta- and para-substituted ethyl benzoates is +2.46; the p value for amide formation for the reaction of a series of meta- and para-substituted anilines with benzoyl chloride is -2.78. OCH,CH3 OCH,CH3 OCH,CH3 ortho-substituted meta-substituted para-substituted a. Why does one set of experiments give a positive p value, whereas the other set of experiments gives a negative p value? b. Why were ortho-substituted compounds not included in the experiment? c. What do you predict the sign of the p value to be for the ionization of a series of meta- and para-substituted benzoic acids?

Information about the mechanism of the reaction undergone by a series of substituted benzenes can be obtained by plotting the logarithm of the observed rate constant determined at a particular pH against the Hammett substituent constant (o) for the particular substituent. The o value for hydrogen is 0. Electron-donating substituents have negative o values; the more strongly electron donating the substituent, the more negative its o value. Electron-withdrawing substituents have positive o values; the more strongly electron withdrawing the substituent, the more positive its o value. The slope of a plot of the logarithm of the rate constant versus o is called the p (rho) value. The p value for the hydroxide-ion-promoted hydrolysis of a series of meta- and para-substituted ethyl benzoates is +2.46; the p value for amide formation for the reaction of a series of meta- and para-substituted anilines with benzoyl chloride is -2.78. OCH,CH3 OCH,CH3 OCH,CH3 ortho-substituted meta-substituted para-substituted a. Why does one set of experiments give a positive p value, whereas the other set of experiments gives a negative p value? b. Why were ortho-substituted compounds not included in the experiment? c. What do you predict the sign of the p value to be for the ionization of a series of meta- and para-substituted benzoic acids?

Chemistry
Chemistry
10th Edition
ISBN:9781305957404
Author:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste
Publisher:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste
Chapter1: Chemical Foundations
Section: Chapter Questions
Problem 1RQ: Define and explain the differences between the following terms. a. law and theory b. theory and...
See similar textbooks
icon
Related questions
Question
Information about the mechanism of the reaction undergone by a series of substituted benzenes can be obtained by plotting the logarithm of the observed rate constant determined at a particular pH against the Hammett substituent constant (o) for the particular substituent. The o value for hydrogen is 0. Electron-donating substituents have negative o values; the more strongly electron donating the substituent, the more negative its o value. Electron-withdrawing substituents have positive o values; the more strongly electron withdrawing the substituent, the more positive its o value. The slope of a plot of the logarithm of the rate constant versus o is called the p (rho) value. The p value for the hydroxide-ion-promoted hydrolysis of a series of meta- and para-substituted ethyl benzoates is +2.46; the p value for amide formation for the reaction of a series of meta- and para-substituted anilines with benzoyl chloride is -2.78. OCH,CH3 OCH,CH3 OCH,CH3 ortho-substituted meta-substituted para-substituted a. Why does one set of experiments give a positive p value, whereas the other set of experiments gives a negative p value? b. Why were ortho-substituted compounds not included in the experiment? c. What do you predict the sign of the p value to be for the ionization of a series of meta- and para-substituted benzoic acids?
Transcribed Image Text:Information about the mechanism of the reaction undergone by a series of substituted benzenes can be obtained by plotting the logarithm of the observed rate constant determined at a particular pH against the Hammett substituent constant (o) for the particular substituent. The o value for hydrogen is 0. Electron-donating substituents have negative o values; the more strongly electron donating the substituent, the more negative its o value. Electron-withdrawing substituents have positive o values; the more strongly electron withdrawing the substituent, the more positive its o value. The slope of a plot of the logarithm of the rate constant versus o is called the p (rho) value. The p value for the hydroxide-ion-promoted hydrolysis of a series of meta- and para-substituted ethyl benzoates is +2.46; the p value for amide formation for the reaction of a series of meta- and para-substituted anilines with benzoyl chloride is -2.78. OCH,CH3 OCH,CH3 OCH,CH3 ortho-substituted meta-substituted para-substituted a. Why does one set of experiments give a positive p value, whereas the other set of experiments gives a negative p value? b. Why were ortho-substituted compounds not included in the experiment? c. What do you predict the sign of the p value to be for the ionization of a series of meta- and para-substituted benzoic acids?
Expert Solution
trending now

Trending now

This is a popular solution!

steps

Step by step

Solved in 5 steps with 7 images

SEE SOLUTIONCheck out a sample Q&A here
Blurred answer
Similar questions
  • SEE MORE QUESTIONS
Recommended textbooks for you
Chemistry
Chemistry
Chemistry
ISBN:
9781305957404
Author:
Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste
Publisher:
Cengage Learning
Chemistry
Chemistry
Chemistry
ISBN:
9781259911156
Author:
Raymond Chang Dr., Jason Overby Professor
Publisher:
McGraw-Hill Education
Principles of Instrumental Analysis
Principles of Instrumental Analysis
Chemistry
ISBN:
9781305577213
Author:
Douglas A. Skoog, F. James Holler, Stanley R. Crouch
Publisher:
Cengage Learning
Organic Chemistry
Organic Chemistry
Chemistry
ISBN:
9780078021558
Author:
Janice Gorzynski Smith Dr.
Publisher:
McGraw-Hill Education
Chemistry: Principles and Reactions
Chemistry: Principles and Reactions
Chemistry
ISBN:
9781305079373
Author:
William L. Masterton, Cecile N. Hurley
Publisher:
Cengage Learning
Elementary Principles of Chemical Processes, Bind…
Elementary Principles of Chemical Processes, Bind…
Chemistry
ISBN:
9781118431221
Author:
Richard M. Felder, Ronald W. Rousseau, Lisa G. Bullard
Publisher:
WILEY
SEE MORE TEXTBOOKS