Textbook Question
What orbitals contain the electrons represented as lone pairs in the structures of quinoline, indole, imidazole?
1670
views
Ch. 8 - Delocalized Electrons: Their Effect on Stability, pKa, and the Products of a Reaction • Aromaticity and Electronic Effects: An Introduction to the Reactions of Benzene
Bruice8th EditionOrganic ChemistryISBN: 9780135213711
Not the one you use?Change textbookSelect a different textbook
Table of contents
- Ch. 1 - Remembering General Chemistry: Electronic Structure and Bonding (Part 1)31
- Ch. 1 - Remembering General Chemistry: Electronic Structure and Bonding (Part 2)65
- Ch. 2 - Acids and Bases: Central to Understanding Organic Chemistry84
- Ch. 3 - An Introduction to Organic Compounds:Nomenclature, Physical Properties, and Structure183
- Ch. 4 - Isomers: The Arrangement of Atoms in Space121
- Ch. 5 - Alkenes: Structure, Nomenclature, and an Introduction to Reactivity • Thermodynamics and Kinetics83
- Ch. 6 - The Reactions of Alkenes • The Stereochemistry of Addition Reactions175
- Ch. 7 - The Reactions of Alkynes • An Introduction to Multistep Synthesis119
- Ch. 8 - Delocalized Electrons: Their Effect on Stability, pKa, and the Products of a Reaction • Aromaticity and Electronic Effects: An Introduction to the Reactions of Benzene148
- Ch. 9 - Substitution and Elimination Reactions of Alkyl Halides212
- Ch. 10 - Reactions of Alcohols, Ethers, Epoxides, Amines, and Sulfur-Containing Compounds131
- Ch. 11 - Organometallic Compounds60
- Ch. 12 - Radicals90
- Ch. 13 - Mass Spectrometry; Infrared Spectroscopy; UV/Vis Spectroscopy62
- Ch. 14 - NMR Spectroscopy95
- Ch. 15 - Reactions of Carboxylic Acids and Carboxylic Acid Derivatives123
- Ch. 16 - Reactions of Aldehydes and Ketones • More Reactions of Carboxylic Acid Derivatives141
- Ch. 17 - Reactions at the Alpha-Carbon101
- Ch. 18 - Reactions of Benzene and Substituted Benzenes144
- Ch. 19 - More About Amines • Reactions of Heterocyclic Compounds49
- Ch. 20 - The Organic Chemistry of Carbohydrates80
- Ch. 21 - Amino Acids, Peptides, and Proteins57
- Ch. 22 - Catalysis in Organic Reactions and in Enzymatic Reactions35
- Ch. 23 - The Organic Chemistry of the Coenzymes—Compounds Derived from Vitamins1
- Ch. 28 - Pericyclic Reactions58
All textbooks
Bruice 8th EditionCh. 8 - Delocalized Electrons: Their Effect on Stability, pKa, and the Products of a Reaction • Aromaticity and Electronic Effects: An Introduction to the Reactions of BenzeneProblem 56
Bruice 8th EditionCh. 8 - Delocalized Electrons: Their Effect on Stability, pKa, and the Products of a Reaction • Aromaticity and Electronic Effects: An Introduction to the Reactions of BenzeneProblem 56Chapter 9, Problem 56
What orbital do the lone-pair electrons occupy in each of the following compounds?
a. 
b. 
c. 
Verified step by step guidance1
Step 1: Analyze the structure in (i). The compound is CH3CH2CH2NH2, which contains a nitrogen atom with a lone pair of electrons. Nitrogen is sp3 hybridized in this case because it is bonded to three atoms (two hydrogens and one carbon) and has one lone pair. The lone pair occupies an sp3 orbital.
Step 2: Examine the structure in (ii). The compound contains a nitrogen atom bonded to a carbon atom via a double bond (C=N) and a single bond to another carbon atom. Nitrogen in this case is sp2 hybridized because it is bonded to two atoms and has one lone pair. The lone pair occupies an sp2 orbital.
Step 3: Analyze the structure in (iii). The compound contains a nitrogen atom triple-bonded to a carbon atom (C≡N). Nitrogen in this case is sp hybridized because it is bonded to one atom and has one lone pair. The lone pair occupies an sp orbital.
Step 4: Understand the hybridization concept. Hybridization is determined by the number of regions of electron density around the atom. Lone pairs count as one region of electron density, and bonds (single, double, or triple) also count as regions.
Step 5: Summarize the orbital occupancy for the lone pairs: (i) sp3 orbital for CH3CH2CH2NH2, (ii) sp2 orbital for the imine group, and (iii) sp orbital for the nitrile group.
Verified video answer for a similar problem:
This video solution was recommended by our tutors as helpful for the problem above.
Video duration:
4mWas this helpful?
Key Concepts
Here are the essential concepts you must grasp in order to answer the question correctly.
Lone Pair Electrons
Lone pair electrons are pairs of valence electrons that are not involved in bonding and are localized on a single atom. They play a crucial role in determining the geometry and reactivity of molecules. Understanding where these electrons reside helps predict molecular shape and polarity, which are essential for analyzing chemical behavior.
Recommended video:
Guided course
02:33
Determining R and S with Lone Pairs
Hybridization
Hybridization is the concept of mixing atomic orbitals to form new hybrid orbitals that can accommodate bonding and lone pair electrons. The type of hybridization (sp, sp2, sp3) influences the geometry of the molecule. For example, sp hybridization leads to linear geometry, while sp3 results in tetrahedral geometry, affecting how lone pairs are positioned.
Recommended video:
Guided course
10:43Using bond sites to predict hybridization
Orbital Theory
Orbital theory describes the behavior of electrons in atoms and molecules, focusing on the shapes and energies of orbitals. Each type of orbital (s, p, d, f) has a distinct shape and energy level, influencing how electrons are distributed in a molecule. Understanding orbital theory is essential for determining the location of lone pairs and predicting molecular interactions.
Recommended video:
Guided course
16:Review of Atomic Orbitals
Related Practice
Textbook Question
In what direction is the dipole moment in calicene? Explain.
1412
views
Textbook Question
Which of the following compounds could be protonated without destroying its aromaticity?
1287
views
Textbook Question
Following the instructions for drawing the energy levels of the molecular orbitals for the compounds shown in [Figure 8.17], draw the energy levels of the molecular orbitals for the cycloheptatrienyl cation. For each compound, show the distribution of the electrons. Which of the compounds are aromatic?
886
views
Textbook Question
What orbitals contain the electrons represented as lone pairs in the structures of purine, and pyrimidine?
750
views
Textbook Question
Following the instructions for drawing the energy levels of the molecular orbitals for the compounds shown in [Figure 8.17], draw the energy levels of the molecular orbitals for the cycloheptatrienyl cation. For each compound, show the distribution of the electrons. Which of the compounds are aromatic?
856
views