What alkane, with molecular formula C 5 H 12 , forms only one monochlorinated product when it is heated with Cl 2 ?

All right. Hello everyone. So this question says that an all cane has a molecular formula of C eight H 18 and can only form a single product when it reacts with co two under light, draw its structure. Now recall first and foremost that an old cane can react with a diatomic halogen, for example, co two in the presence of light to produce I'll kill highlight this undergoes a radical mechanism. Now, the number of products that can be obtained depends on the structure of the starting alane because one carbon hydrogen bond is replaced with a carbon halogen bond. So depending on how many non equivalent hydrogens, there are multiple different products can be produced. So with this in mind, in order for only one single halogenated product to be produced all of the hydrogens, and therefore all of the carbons that contain those hydrogens must be equivalent. So there has to be an element of symmetry to the compound that we're starting with. Now, it cannot be a straight chain because even though there's symmetry in the molecule, we would end up with four different products considering it would be an eight carbon chain to illustrate this point, I went ahead and I drew octane here to showcase that even though there is a symmetry to this molecule, you would still end up with four unique products. So another possibility would be to shorten the parent chain and add methyl or ethyl substituents. But an ethyl substituent which is RCH two ch three on its own would produce two different products since both carbons of the ethyl group are different. So this means that the carbon chain has to be shortened and methyl groups must be added instead. Now to make sure that all hydrogens are equivalent, there must be the same number of methyl groups on each carbon of the chain. So in this case, we can do a four carbon chain with two additional methyl groups on the 2nd and 3rd carbons notice how this creates two ordinary carbons that don't have their own hydrogens and therefore cannot be chlorinated. And each ordinary carbon has three identical metal groups due to that symmetry. So our answer here would be 2233 tetra methyl butane and there you have it. So with that being said, thank you so very much for watching. And I hope you found this helpful.

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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

11. Radical Reactions

Free Radical Halogenation

Organic Chemistry

11. Radical Reactions

Free Radical Halogenation

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Problem 27a

Textbook Question

What alkane, with molecular formula C₅H₁₂, forms only one monochlorinated product when it is heated with Cl₂?

Verified step by step guidance

Identify the molecular formula of the alkane, C5H12, which corresponds to a saturated hydrocarbon with 5 carbon atoms and 12 hydrogen atoms.

Recall that for an alkane to form only one monochlorinated product, all the hydrogen atoms in the molecule must be equivalent. This means the alkane must have a symmetrical structure.

Consider the possible isomers of C5H12: pentane (straight-chain), isopentane (branched with one methyl group), and neopentane (branched with two methyl groups).

Analyze the symmetry of each isomer: Pentane and isopentane have multiple types of hydrogen atoms (primary, secondary, tertiary), leading to multiple monochlorinated products. Neopentane, however, has all 12 hydrogens equivalent due to its high symmetry.

Conclude that the alkane with molecular formula C5H12 that forms only one monochlorinated product is neopentane (2,2-dimethylpropane).

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Key Concepts

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

Alkanes

Alkanes are saturated hydrocarbons consisting only of carbon and hydrogen atoms, connected by single bonds. They follow the general formula CnH2n+2, where 'n' is the number of carbon atoms. The structure of alkanes can vary from straight-chain to branched forms, influencing their chemical reactivity and properties.

Monochlorination

Monochlorination is a substitution reaction where one hydrogen atom in an alkane is replaced by a chlorine atom, typically using chlorine gas (Cl2) under heat or light. The process can lead to multiple products if the alkane has different hydrogen atoms that can be substituted, but some alkanes yield only one product due to their symmetrical structure.

Symmetry in Organic Molecules

Symmetry in organic molecules refers to the arrangement of atoms that allows for identical environments for certain substituents. In the case of alkanes, a symmetrical structure means that all hydrogen atoms are equivalent, leading to only one possible product during reactions like chlorination. This concept is crucial for predicting the outcomes of substitution reactions.

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