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

Electronegativity

Organic Chemistry

1. A Review of General Chemistry

Electronegativity

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4:59 minutes

Problem 46a

Textbook Question

For each alkene, indicate the direction of the dipole moment. For each pair, determine which compound has the larger dipole moment.
a. cis-1,2-difluoroethene or trans-1,2-difluoroethene

Verified step by step guidance

Identify the molecular structure of cis-1,2-difluoroethene and trans-1,2-difluoroethene. In the cis isomer, both fluorine atoms are on the same side of the double bond, while in the trans isomer, they are on opposite sides.

Understand that the dipole moment is a vector quantity that depends on the difference in electronegativity between atoms and the geometry of the molecule. Fluorine is more electronegative than carbon, creating a dipole in the C-F bond.

For cis-1,2-difluoroethene, the dipole moments of the two C-F bonds add up because they are in the same direction, resulting in a net dipole moment pointing from the hydrogen side towards the fluorine side.

For trans-1,2-difluoroethene, the dipole moments of the two C-F bonds cancel each other out because they are in opposite directions, resulting in a net dipole moment of zero.

Compare the net dipole moments: cis-1,2-difluoroethene has a larger dipole moment than trans-1,2-difluoroethene because the dipoles in the trans isomer cancel out, while in the cis isomer, they reinforce each other.

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Key Concepts

Here are the essential concepts you must grasp in order to answer the question correctly.

Dipole Moment

The dipole moment is a measure of the separation of positive and negative charges in a molecule. It is a vector quantity, having both magnitude and direction, and is influenced by the electronegativity of atoms and the geometry of the molecule. In alkenes, the dipole moment is determined by the arrangement of substituents around the double bond.

Cis-Trans Isomerism

Cis-trans isomerism, also known as geometric isomerism, occurs in alkenes due to restricted rotation around the double bond. In cis isomers, similar groups are on the same side of the double bond, while in trans isomers, they are on opposite sides. This spatial arrangement affects the dipole moment, as cis isomers often have a higher dipole moment due to the additive effect of the dipoles.

Electronegativity

Electronegativity is the tendency of an atom to attract electrons towards itself in a chemical bond. In molecules like difluoroethene, fluorine's high electronegativity creates a polar bond with carbon, contributing to the molecule's overall dipole moment. The difference in electronegativity between bonded atoms is a key factor in determining the direction and magnitude of the dipole moment.

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For each alkene, indicate the direction of the dipole moment. For each pair, determine which compound has the larger dipole moment.a. cis-1,2-difluoroethene or trans-1,2-difluoroethene

Key Concepts

Dipole Moment

Cis-Trans Isomerism

Electronegativity

Watch next

For each alkene, indicate the direction of the dipole moment. For each pair, determine which compound has the larger dipole moment.
a. cis-1,2-difluoroethene or trans-1,2-difluoroethene