Textbook Question
Consider the following compounds that vary from nearly nonacidic to strongly acidic. Draw the conjugate bases of these compounds, and explain why the acidity increases so dramatically with substitution by nitro groups.
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Ch. 2 - Acids and Bases; Functional Groups
Wade9th EditionOrganic ChemistryISBN: 9780135213728
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Table of contents
- Ch.1 - Structure and Bonding107
- Ch. 2 - Acids and Bases; Functional Groups115
- Ch.3 - Structure and Stereochemistry of Alkanes100
- Ch.4 - The Study of Chemical Reactions99
- Ch.5 - Stereochemistry93
- Ch.6 - Alkyl Halides; Nucleophilic Substitution118
- Ch. 7 - Structure and Synthesis of Alkenes; Elimination158
- Ch.8 - Reactions of Alkenes171
- Ch.9 - Alkynes91
- Ch.10 - Structure and Synthesis of Alcohols143
- Ch.11 - Reactions of Alcohols104
- Ch. 12 - Infrared Spectroscopy and Mass Spectrometry22
- Ch. 13 - Nuclear Magnetic Resonance Spectroscopy45
- Ch. 14 - Ethers, Epoxides, and Thioethers72
- Ch. 15 - Conjugated Systems, Orbital Symmetry, and Ultraviolet Spectroscopy89
- Ch. 16 - Aromatic Compounds74
- Ch. 17 - Reactions of Aromatic Compounds126
- Ch. 18 - Ketones and Aldehydes193
- Ch. 19 - Amines129
- Ch. 20 - Carboxylic Acids77
- Ch. 21 - Carboxylic Acid Derivatives141
- Ch. 22 - Condensations and Alpha Substitutions of Carbonyl Compounds175
- Ch. 23 - Carbohydrates and Nucleic Acids93
- Ch. 24 - Amino Acids, Peptides, and Proteins54
Chapter 2, Problem 47b
The following compounds can all react as acids.
b. Rank the conjugate bases in the order you would predict, from most stable to least stable.
Verified step by step guidance1
Identify the conjugate base for each acid by removing a proton (H⁺) from the acidic hydrogen. This will result in a negatively charged species for each compound.
Consider the stability of each conjugate base. Stability is often influenced by factors such as electronegativity, resonance, and inductive effects.
Evaluate the electronegativity of the atoms bearing the negative charge. More electronegative atoms can better stabilize the negative charge.
Assess the resonance stabilization. Conjugate bases that can delocalize the negative charge through resonance are generally more stable.
Consider any inductive effects. Electronegative atoms or groups near the negative charge can stabilize it through inductive effects, enhancing the stability of the conjugate base.
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Key Concepts
Here are the essential concepts you must grasp in order to answer the question correctly.
Acid-Base Chemistry
In organic chemistry, acids are substances that can donate a proton (H+), and their strength is often determined by the stability of their conjugate base. The more stable the conjugate base, the stronger the acid. This stability is influenced by factors such as electronegativity, resonance, and inductive effects.
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02:49
The Lewis definition of acids and bases.
Conjugate Base Stability
The stability of a conjugate base is crucial in determining the acidity of a compound. A stable conjugate base is less likely to re-accept a proton, making the original compound a stronger acid. Stability can be enhanced by resonance, where the negative charge is delocalized, or by electronegative atoms that can stabilize the charge through inductive effects.
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04:31Stability of Conjugated Intermediates
Inductive and Resonance Effects
Inductive effects involve the transmission of charge through a chain of atoms in a molecule, often influenced by electronegative atoms like fluorine. Resonance effects involve the delocalization of electrons across multiple atoms, stabilizing the conjugate base. Both effects play a significant role in determining the acidity of a compound by affecting the stability of its conjugate base.
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01:47Understanding the Inductive Effect.
Related Practice
Textbook Question
The following compounds can all react as bases.
c. Rank the original compounds in order, from strongest base to weakest base.
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Textbook Question
Methyllithium (CH3Li) is often used as a base in organic reactions.
b. What is the conjugate acid of CH3Li? Would you expect CH3Li to be a strong base or a weak base?
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Textbook Question
The following compounds can all react as acids.
a. For each compound, show its conjugate base. Show any resonance forms if applicable.
Textbook Question
The following compounds can all react as bases.
b. Rank the conjugate acids in the order you would predict, from most stable to least stable.
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Textbook Question
Label the reactants in these acid–base reactions as Lewis acids (electrophiles) or Lewis bases (nucleophiles). Use curved arrows to show the movement of electron pairs in the reactions.
(a)