Textbook Question
Draw the important resonance forms for the following molecules and ions.
(a) CO32–
(b)
(c)
1311
views
Ch.1 - Structure and Bonding
Wade9th EditionOrganic ChemistryISBN: 9780135213728
Not the one you use?Change textbookSelect a different textbook
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 1, Problem 6i-l
Draw Lewis structures for the following compounds and ions, showing appropriate formal charges.
(i) (CH3)2O—BF3
(j) [HONH3]+
(k) KOC(CH3)3
(l) [H2C=OH]+
Verified step by step guidance1
Step 1: Begin by identifying the total number of valence electrons for each compound or ion. For (CH3)2O—BF3, calculate the valence electrons from carbon, hydrogen, oxygen, and boron. For [HONH3]+, consider the valence electrons from hydrogen, oxygen, and nitrogen, and account for the positive charge. For KOC(CH3)3, include potassium, oxygen, and carbon. For [H2C=OH]+, consider hydrogen, carbon, and oxygen, and account for the positive charge.
Step 2: Arrange the atoms in a skeletal structure. Typically, the least electronegative atom is central. For (CH3)2O—BF3, oxygen is central between the two CH3 groups, and boron is attached to oxygen. For [HONH3]+, nitrogen is central with hydrogen and oxygen attached. For KOC(CH3)3, carbon is central with oxygen and potassium attached. For [H2C=OH]+, carbon is central with hydrogen and oxygen attached.
Step 3: Distribute the valence electrons around the atoms to satisfy the octet rule (or duet for hydrogen). Start by placing electrons as bonds between atoms, then distribute remaining electrons as lone pairs. For (CH3)2O—BF3, ensure boron has only six electrons as it is an exception to the octet rule. For [HONH3]+, ensure nitrogen has a full octet. For KOC(CH3)3, ensure carbon has a full octet. For [H2C=OH]+, ensure carbon and oxygen have full octets.
Step 4: Assign formal charges to each atom. Formal charge is calculated using the formula: Formal Charge = (Valence Electrons) - (Non-bonding Electrons) - (Bonding Electrons/2). Calculate the formal charge for each atom in the structures to ensure the overall charge matches the given charge of the compound or ion.
Step 5: Verify the stability of the Lewis structures. Check that the formal charges are minimized and that the structure adheres to the rules of chemical bonding. Adjust the structure if necessary to achieve the most stable configuration, ensuring that the total charge of the molecule or ion is correct.
Verified video answer for a similar problem:
This video solution was recommended by our tutors as helpful for the problem above.
Video duration:
11mWas this helpful?
Key Concepts
Here are the essential concepts you must grasp in order to answer the question correctly.
Lewis Structures
Lewis structures are diagrams that represent the bonding between atoms of a molecule and the lone pairs of electrons that may exist. They are essential for visualizing the arrangement of atoms, the distribution of electrons, and the formal charges in a molecule. Understanding how to draw Lewis structures involves knowing the valence electrons for each atom and applying the octet rule where applicable.
Recommended video:
Guided course
04:12
Drawing the Lewis Structure for N2H4.
Formal Charge
Formal charge is a theoretical charge assigned to an atom in a molecule, calculated by assuming equal sharing of electrons in bonds. It is determined using the formula: Formal Charge = (Valence Electrons) - (Non-bonding Electrons) - (Bonding Electrons/2). Calculating formal charges helps in identifying the most stable Lewis structure by minimizing the charges across the molecule.
Recommended video:
Guided course
01:34Calculating formal and net charge.
Resonance Structures
Resonance structures are different Lewis structures for the same molecule that depict the delocalization of electrons. They are used when a single Lewis structure cannot accurately represent the electron distribution. Resonance structures are important for understanding the stability and reactivity of molecules, as the true structure is a hybrid of all possible resonance forms.
Recommended video:
Guided course
03:04Drawing Resonance Structures
Related Practice
Textbook Question
Use electronegativities to predict the direction of the dipole moments of the following bonds.
(f) N—Cl
(g) N—O
(h) N—S
(i) N—B
(j) B—Cl
2459
views
Textbook Question
Draw the important resonance forms for the following molecules and ions.
(d) NO3–
(e) NO2–
(f)
1278
views
Textbook Question
Draw Lewis structures for the following compounds and ions, showing appropriate formal charges.
(e) +CH3
(f) –CH3
(g) NaBH4
(h) NaBH3CN
2205
views
Textbook Question
For each of the following compounds, draw the important resonance forms. Indicate which structures are major and minor contributors or whether they have the same energy.
(c) [H2COCH3]+
757
views
Textbook Question
Write Lewis structures for the following molecular formulas. Circle any lone pairs (pairs of nonbonding electrons) in the structures.
i. C3H6 (one double bond)
j. C3H4 (two double bonds)
k. C3H4 (one triple bond)
2318
views