a. How many linear dienes have molecular formula C 6 H 10 ? (Disregard cis–trans isomers.) b. How many of the linear dienes in part a are conjugated dienes?

Hello everyone. Let's do this problem together. It says determine the number of linear Dynes consistent with the formula C seven H 12 do not include stereo isomers. How many of these are conjugated Dynes? All right. So we want linear Dynes. So that means we have no rings and we don't want to include stereo isomers. So with the double bonds, the alkenes, if we were considering stereo isomers, that would be the E and Z configuration, right? So we are not considering E or Z configuration. And we also want to determine the number of conjugated Dynes. So we call that a conjugated dying is two double bonds, right? A dye and they are Dynes. And that means they have zero carbons between those two double bonds. So an example of a simple dying would be a four carbon chain. And when I say 13 dying, that means the first double bond starts on carbon one and goes to carbon two, second, double bond starts on carbon three and goes to carbon four. So that is an example of a conjugated dying. So let's start drawing as many linear Dynes as we can with the formula C seven H 12. So we know we have to have a seven carbon chain. So let's draw a seven carbon zigzag chain 1234567. And we'll start with carbon one and carbon three, right? So let's draw the next one and we'll keep the first double bond on carbon one and we'll just move that carbon bond down the chain, right. We're not looking at conjugated Dynes yet, just all the possible linear Dynes. So now we can start that next double bond on carbon four. All right, next one, let's start the second double bond on carbon five and lastly start the second double bond on carbon six. So we have 131415 and substituted, dying. All right. So now let's move that first double bond two, carbon two and we'll move the second double bond to carbon four. OK? We can't put them right next to each other, right? That would violate the octet or the nature of a hydrocarbon chain. So for the next one, we will keep the first double bond on carbon two, move the second one to carbon five. And let's see, that's all we can do if we keep the first double bond on carbon two. If I tried to draw another structure and move the double bond to carbon three and then draw a conjugated dying. Notice that this is the same structure as the fifth one that I drew where we have the 24 dying. So let me number this to show you 1234. If we number our structure correctly, we notice that it is the same structure. OK. So this does not count as a new one. So that means we can draw six linear Dynes, right? If we keep trying to move that double bond down and do the same pattern that we just did, we're going to get repeat structures. So these are our six linear Dynes. So now how many of these are conjugated are 13 Dynes? While the first structure, the 13 hep to dying is a dying, a conjugated dying. And our fifth structure where the double bonds are on carbons, two and four is also a conjugated dying. So we have six linear Dynes and two conjugated Dynes. So that is the correct answer for this problem. And that's it for this video. I hope this was helpful and I'll see you soon.

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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

Conjugation Chemistry

Organic Chemistry

16. Conjugated Systems

Conjugation Chemistry

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8:54 minutes

Problem 67a,b

Textbook Question

a. How many linear dienes have molecular formula C₆H₁₀? (Disregard cis–trans isomers.)
b. How many of the linear dienes in part a are conjugated dienes?

Verified step by step guidance

Step 1: Understand the molecular formula C6H10. This formula represents a hydrocarbon with six carbon atoms and ten hydrogen atoms. Since it is a diene, it contains two double bonds. The molecule must be linear, meaning no branching is allowed.

Step 2: Determine the degree of unsaturation for C6H10. Use the formula for degree of unsaturation: \( ext{Degree of Unsaturation} = rac{2C + 2 - H}{2} \), where \( C \) is the number of carbon atoms and \( H \) is the number of hydrogen atoms. For C6H10, calculate \( ext{Degree of Unsaturation} = rac{2(6) + 2 - 10}{2} = 2 \). This indicates two double bonds or one ring and one double bond.

Step 3: Enumerate all possible linear structures with two double bonds. Since the molecule is linear, the double bonds can be placed in different positions along the carbon chain. Disregard cis-trans isomers, focusing only on connectivity. Consider all possible arrangements of the double bonds while ensuring the molecule remains linear and satisfies the molecular formula.

Step 4: Identify conjugated dienes among the structures. Conjugated dienes are characterized by alternating single and double bonds (e.g., \( -C=C-C=C- \)). Examine each structure from Step 3 to determine if the double bonds are conjugated or isolated (separated by more than one single bond).

Step 5: Count the total number of linear dienes and the subset of conjugated dienes. Ensure all structures satisfy the molecular formula and are linear. Summarize the findings for part a (total linear dienes) and part b (conjugated dienes).

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Key Concepts

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

Dienes

Dienes are organic compounds that contain two double bonds. They can be classified into different types based on the arrangement of these double bonds, such as isolated, conjugated, and cumulated dienes. Understanding the structure and classification of dienes is essential for determining their properties and reactivity.

Molecular Formula and Structural Isomers

The molecular formula C6H10 indicates that the compound contains six carbon atoms and ten hydrogen atoms. Structural isomers are compounds that have the same molecular formula but different arrangements of atoms. Identifying all possible linear structures that fit this formula is crucial for answering the question about the number of linear dienes.

Conjugated Dienes

Conjugated dienes are a specific type of diene where the double bonds are separated by a single bond, allowing for delocalization of electrons. This delocalization can affect the stability and reactivity of the compound. Recognizing which of the linear dienes are conjugated is important for understanding their chemical behavior and properties.

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