Table of contents

1. A Review of General Chemistry5h 5m
2. Molecular Representations1h 14m
3. Acids and Bases2h 46m
4. Alkanes and Cycloalkanes4h 17m
5. Chirality3h 39m
6. Thermodynamics and Kinetics1h 22m
7. Substitution Reactions1h 48m
8. Elimination Reactions2h 30m
9. Alkenes and Alkynes2h 9m
10. Addition Reactions3h 19m
11. Radical Reactions1h 58m
12. Alcohols, Ethers, Epoxides and Thiols2h 42m
13. Alcohols and Carbonyl Compounds2h 17m
14. Synthetic Techniques1h 26m
15. Analytical Techniques:IR, NMR, Mass Spect7h 3m
16. Conjugated Systems6h 13m
17. Ultraviolet Spectroscopy51m
18. Aromaticity2h 34m
19. Reactions of Aromatics: EAS and Beyond5h 1m
20. Phenols55m
21. Aldehydes and Ketones: Nucleophilic Addition4h 56m
22. Carboxylic Acid Derivatives: NAS2h 51m
23. The Chemistry of Thioesters, Phophate Ester and Phosphate Anhydrides1h 10m
24. Enolate Chemistry: Reactions at the Alpha-Carbon1h 53m
25. Condensation Chemistry2h 9m
26. Amines1h 43m
27. Heterocycles2h 0m
28. Carbohydrates5h 53m
29. Amino Acids4h 20m
30. Peptides and Proteins2h 42m
31. Catalysis in Organic Reactions1h 30m
32. Lipids 2h 50m
33. The Organic Chemistry of Metabolic Pathways2h 52m
34. Nucleic Acids1h 32m
35. Transition Metals6h 14m
36. Synthetic Polymers1h 49m

1. A Review of General Chemistry

Lewis Structure

Organic Chemistry

1. A Review of General Chemistry

Lewis Structure

Previous problemNext problem

2:50 minutes

Problem 79a

Textbook Question

In addition to radicals, anions, and cations, a fourth class of reactive intermediates is carbenes. A neutral species, the simplest carbene has a molecular formula of CH₂.
(a) Draw the Lewis structure of CH₂.

Verified step by step guidance

Step 1: Begin by identifying the molecular formula CH₂. This indicates that the molecule contains one carbon atom and two hydrogen atoms.

Step 2: Recall that carbon has four valence electrons and hydrogen has one valence electron. The total number of valence electrons in CH₂ is calculated as follows: Carbon contributes 4 electrons, and each hydrogen contributes 1 electron, giving a total of 4 + 1 + 1 = 6 valence electrons.

Step 3: Arrange the atoms with carbon as the central atom, since it is less electronegative than hydrogen. Connect the two hydrogen atoms to the carbon atom using single bonds. Each single bond represents two shared electrons.

Step 4: After forming the two single bonds, 4 electrons are used (2 electrons per bond). This leaves 2 valence electrons remaining. Place these remaining electrons as a lone pair on the carbon atom.

Step 5: Verify the structure by checking the formal charges and ensuring that the total number of valence electrons matches the calculated total. Carbon will have a lone pair and two single bonds, making it neutral, and each hydrogen atom will have a full valence shell with 2 electrons.

Verified video answer for a similar problem:

This video solution was recommended by our tutors as helpful for the problem above

Video duration:

Play a video:

Was 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 in a molecule and the lone pairs of electrons that may exist. They help visualize the arrangement of electrons and the connectivity of atoms, which is crucial for understanding molecular geometry and reactivity. In the case of CH₂, the Lewis structure will show how the carbon atom is bonded to two hydrogen atoms and the distribution of its valence electrons.

Carbenes

Carbenes are neutral reactive intermediates that contain a carbon atom with only six valence electrons, resulting in a divalent state. They can be classified as singlet or triplet carbenes based on the spin state of their unpaired electrons. Understanding carbenes is essential for grasping their role in organic reactions, as they can act as nucleophiles or electrophiles depending on their electronic configuration.

Valence Electrons

Valence electrons are the outermost electrons of an atom and are crucial for chemical bonding. In the context of CH₂, carbon has four valence electrons, while each hydrogen has one. The arrangement and sharing of these electrons determine the molecule's structure and stability, making it important to account for them when drawing Lewis structures and predicting molecular behavior.

Watch next

Master How to use Organic Chemistry to make Lewis Structures easier. with a bite sized video explanation from Johnny

Start learning