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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

16. Conjugated Systems

Stability of Conjugated Intermediates

Organic Chemistry

16. Conjugated Systems

Stability of Conjugated Intermediates

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Multiple Choice

Which of the following trienes has the lowest heat of hydration (ΔH°_hydr)?

The figure illustrates the structure of a molecule. An 8-carbon alkene chain is depicted as a line structure using 7 zigzag lines. A double bond is present between C 1 and C 2, C 4 and C 5, and C 7 and C 8.

The figure illustrates the structure of a molecule. A 3-carbon alkane chain is depicted as a line structure using 2 zigzag lines. C 3 is double bonded to a C atom on the upper right. The C atom is double bonded to a second C atom on the upper right. The second C atom is double bonded on the upper right to C 1 of a second 3-carbon alkane chain depicted as a line structure using 2 zigzag lines.

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Verified step by step guidance

Identify the degree of conjugation in each triene. Conjugated systems have alternating single and double bonds, which can stabilize the molecule and lower the heat of hydration.

Examine the first structure: It has isolated double bonds, meaning they are not conjugated. This typically results in a higher heat of hydration.

Examine the second structure: It also has isolated double bonds, similar to the first structure, leading to a higher heat of hydration.

Examine the third structure: It has conjugated double bonds, which can stabilize the molecule through resonance, potentially resulting in a lower heat of hydration.

Compare the structures: The triene with the most conjugation (third structure) is likely to have the lowest heat of hydration due to increased stability from resonance.