Skip to main content
Ch. 2 - Acids and Bases; Functional Groups
Wade - Organic Chemistry 9th Edition
Wade9th EditionOrganic ChemistryISBN: 9780135213728Non è quello che usi tu?Cambia libro di testo
Capitolo 2, Problema 1b

The C=O double bond has a dipole moment of about 2.4 D and a bond length of about 1.23 Å.
b. Use this information to evaluate the relative importance of the following two resonance contributors:

Guida verificata passo dopo passo
1
Identify the two resonance structures for the given molecule. The first structure has a double bond between the carbon and oxygen, while the second structure has a single bond with a negative charge on oxygen and a positive charge on carbon.
Understand that resonance structures are a way to represent the delocalization of electrons in a molecule. The actual structure is a hybrid of these resonance forms.
Evaluate the dipole moment and bond length information provided. A dipole moment of 2.4 D and a bond length of 1.23 Å suggest a significant contribution from the polar resonance structure.
Consider the stability of each resonance structure. The structure with the double bond (C=O) is generally more stable due to the full octet on both atoms and no formal charges.
Conclude that while both resonance structures contribute to the overall hybrid, the structure with the double bond is likely more important due to its stability and the given dipole moment and bond length, which align more closely with this structure.

Risposta video verificata per un problema simile:

Questa soluzione video è stata consigliata dai nostri tutor come utile per risolvere questo problema.
Durata del video:
5m

Concetti chiave

Ecco i concetti essenziali che devi comprendere per rispondere correttamente alla domanda.

Resonance Structures

Resonance structures are different ways of drawing the same molecule that illustrate the delocalization of electrons. They help in understanding the actual electronic structure of a molecule, which is a hybrid of all possible resonance forms. In the context of the question, the two resonance contributors depict how the C=O bond can be represented with different charges and electron distributions, affecting the molecule's stability and reactivity.
Video consigliato:
03:04
Drawing Resonance Structures

Dipole Moment

The dipole moment is a measure of the separation of positive and negative charges in a molecule, indicating its polarity. A higher dipole moment suggests a stronger polar character, which can influence the molecule's interactions and stability. In this case, the C=O bond's dipole moment of 2.4 D indicates significant polarity, which is essential for evaluating the resonance contributors' relative importance.
Video consigliato:
01:46
How dipole-dipole forces work.

Bond Length

Bond length is the distance between the nuclei of two bonded atoms, which can provide insights into bond strength and stability. A bond length of 1.23 Å for the C=O double bond suggests a strong interaction due to the overlap of atomic orbitals. Understanding bond length is crucial when evaluating resonance structures, as it can indicate how electron delocalization affects the overall stability of the molecule.
Video consigliato:
06:00
Single bonds, double bonds, and triple bonds.