Draw the structure and give the systematic name for a compound with molecular formula C 5 H 12 that has (a) only primary and secondary hydrogens.

Welcome back everyone. What is the structure of a compound with the molecular formula? C 614 that only contains primary and secondary hydrogens? What is its systematic name? Now, there are multiple ways to begin this problem. But of course, we want to make sure that we understand that there are no double bonds or ranks in the structure. Of course, there are no triple bonds as well because both double bonds and triple bonds correspond to a presence of a pi bond. Right? How do we know that? Well, essentially, if we look at the structure, we have a form of CNH two N plus two. And this is an L cane. In this case, M is equal to six, right? The general molecular formula of an L cane satisfies C sex age 14. Because if NS six, then we have CS six H two multiplied by six plus two gives us 14. On the other hand, we can use the formula of hydrogen deficiency index. We take one half multiplied by two, multiplied by the number of carbon atoms plus two minus the number of hydrogens 12 plus two is 1414 minus 14 is +00. Divided by two is zero. So we have no pie bonds, no ranks. This means we have an L cane, right? So now our next requirement is this, the structure must only contain primary and secondary hydrogens. So a primary hydrogen would be a hydrogen atom bonded to a primary carbon. A secondary hydrogen would be a hydrogen bonded to a secondary carbon. So let's start drawing the structure. First of all, if we have an L cane with six carbon atoms, we can draw hexane 123456 carbo nanos, we can of course, start branching it. What if we draw a five member chain and simply add a muscle group to any other position? Well, whenever we start branching it, we notice that we end up with tertiary carbons and we must only have primary and secondary carbons for the first structure. We have a primary carbon atom for the muscle group because that carbon atom only has one neighboring carbon, which is also true for the carbon. At the end, the metal group has a primary carbon, all of the other carbon atoms are secondary ones because all of them have two neighboring carbon atoms. So the first structure satisfies the requirements. While the second one or any other one that has branching would not satisfy the requirements because we would end up with tertiary carbons. And we cannot have that right, because a tertiary carbon would also have a tertiary hydrogen. So that means one of the possibilities for us is to use a straight chain al cane. What is the name of that al cane? Well, it's hexane because it consists of six carbon atoms in the longest continuous chain. And therefore, we can say that the answer to this problem would be Hexane. Thank you for watching.

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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

4. Alkanes and Cycloalkanes

Naming Alkenes

Organic Chemistry

4. Alkanes and Cycloalkanes

Naming Alkenes

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4:25 minutes

Problem 14a

Textbook Question

Draw the structure and give the systematic name for a compound with molecular formula C₅H₁₂ that has
(a) only primary and secondary hydrogens.

Verified step by step guidance

Step 1: Understand the molecular formula C5H12. This formula represents an alkane, which is a saturated hydrocarbon containing only single bonds between carbon atoms.

Step 2: Recognize the requirement for the compound to have only primary and secondary hydrogens. Primary hydrogens are attached to primary carbons (carbons bonded to only one other carbon), and secondary hydrogens are attached to secondary carbons (carbons bonded to two other carbons). This means the structure cannot contain tertiary hydrogens (attached to tertiary carbons).

Step 3: Begin by constructing a straight-chain alkane with five carbons (pentane). In this structure, all hydrogens are either primary or secondary because the terminal carbons have primary hydrogens, and the internal carbons have secondary hydrogens.

Step 4: Verify the structure by counting the hydrogens on each carbon atom to ensure the molecular formula matches C5H12. Each carbon should follow the valency rule of forming four bonds.

Step 5: Assign the systematic name to the compound. Since the structure is a straight-chain alkane with five carbons, the name is 'pentane'.

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Key Concepts

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

Hydrocarbon Structure

Hydrocarbons are organic compounds consisting solely of carbon (C) and hydrogen (H) atoms. The structure of a hydrocarbon can vary significantly based on the arrangement of these atoms, leading to different types of isomers. In the case of C5H12, understanding the structural possibilities, including straight-chain and branched forms, is essential for identifying the correct compound that meets the criteria of having only primary and secondary hydrogens.

Primary and Secondary Hydrogens

Hydrogens in organic compounds are classified based on the type of carbon atom they are attached to. Primary hydrogens are attached to a primary carbon (a carbon bonded to only one other carbon), while secondary hydrogens are attached to secondary carbons (a carbon bonded to two other carbons). For the compound C5H12, recognizing which hydrogens are primary or secondary is crucial for determining the correct structure and ensuring it meets the specified criteria.

Systematic Naming (IUPAC Nomenclature)

IUPAC nomenclature is a systematic method for naming organic compounds based on their structure. The name reflects the number of carbon atoms, the type of bonds, and the presence of functional groups. For the compound C5H12, understanding how to apply IUPAC rules will help in accurately naming the compound, ensuring that the name corresponds to the structure drawn, particularly when distinguishing between different isomers.

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