List each set of compounds in order of increasing boiling point. b. Octane, (CH 3 ) 3 C—C(CH 3 ) 3 and CH 3 CH 2 C(CH 3 ) 2 CH 2 CH 2 CH 3

All right. Hi everyone. So for this question, let's arrange the given compound in decreasing order of the boiling point. So going from highest to lowest. Now, before we discuss these molecules individually, let's recall that the boiling point of a substance depends on the strength of its inter molecular forces or I M F for short, right? And recall that the strongest inter molecular force is hydrogen bonding and hydrogen bonding requires both a donor and an accepted. So hydrogen bond donors are electro negative atoms that have hydrogen attached to them. So think flooring and hydrogen oxygen, hydrogen or nitrogen, hydrogen and your hydrogen bond except ear's are those hydrogen that are bonded directly to those highly electro negative atoms. So to elaborate more on this, right, recall it, the more hydrogen bond forming atoms you have in your molecule, the stronger hydrogen bonding is going to be and therefore the higher boiling point you're going to have, right? So if I go ahead and I make a list from highest to lowest boiling point on the bottom here, what I want to bring to your attention is that molecule a has three hydrogen bond forming atoms which is the most of all these molecules that we're looking at for this question, right? Because molecule A has three nitrogen, each of which has a hydrogen. So hydrogen bonding is in fact possible at these three locations. So that means compound A is capable of the strongest hydrogen bonds and therefore it's going to have the highest boiling point. So if molecule is the highest, then molecule B here is going to be second place, right? Because molecule B has to hydrogen bond forming atoms instead of three. So now with that being said, let's go ahead and compare molecules C and D because both of these molecules have just one hydrogen bond forming Adam, but they're different in terms of their identity, right? So that's going to change the strength of each individual hydrogen bond. So recall really quickly that oxygen is more electro negative than hydrogen. So it's hydrogen bonds are going to be stronger than that of nitrogen. And therefore that one oxygen on molecule D is going to have a higher boiling point Then the one nitrogen on molecule seat. So now we can go ahead and focus our attention on molecules E and F and molecules E N F R hydrocarbon chains. So recall that for hydrocarbon chains, Vander Waals forces are going to predominate. So the question then becomes which of these has stronger Vander Waals interactions. And the answer is actually going to be molecule because recall that Van der Waals forces are stronger when you have a greater surface area in your molecule, right? So because the carbon chain of molecules E is longer than that of molecule F. It's van der Waals forces are going to be stronger because they take up a larger surface area. So molecule F is actually going to have the lowest boiling point here. And so with that being said, um your answer is going to correspond to option A in the multiple choice. So that's going to be if this question, right molecule is going to have your highest boiling point because if I am, if you're stronger, do the sorry due to the presence of those three hydrogen bond forming sites. And by contrast, molecule F is going to have the lowest boiling point because it's Vander Waals forces are the weakest. So with that being said, thank you 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

2. Molecular Representations

Intermolecular Forces

Organic Chemistry

2. Molecular Representations

Intermolecular Forces

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Problem 10b

Textbook Question

List each set of compounds in order of increasing boiling point.
b. Octane, (CH₃)₃C—C(CH₃)₃ and CH₃CH₂C(CH₃)₂CH₂CH₂CH₃

Verified step by step guidance

Understand that boiling point is influenced by molecular weight, intermolecular forces, and molecular structure. Larger molecules and those with stronger intermolecular forces typically have higher boiling points.

Identify the molecular structure of each compound: Octane (C8H18) is a straight-chain alkane, (CH3)3C—C(CH3)3 is 2,2,3,3-tetramethylbutane, a highly branched alkane, and CH3CH2C(CH3)2CH2CH2CH3 is 2,2-dimethylhexane, a less branched alkane.

Consider the effect of branching on boiling point: Straight-chain alkanes generally have higher boiling points than branched alkanes due to greater surface area allowing for stronger van der Waals forces.

Compare the molecular weights: Octane has a molecular weight of 114 g/mol, 2,2,3,3-tetramethylbutane has a molecular weight of 114 g/mol, and 2,2-dimethylhexane has a molecular weight of 114 g/mol. Since the molecular weights are similar, focus on branching.

Arrange the compounds in order of increasing boiling point based on branching: 2,2,3,3-tetramethylbutane (most branched, lowest boiling point), 2,2-dimethylhexane (less branched), and octane (straight-chain, highest boiling point).

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Key Concepts

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

Boiling Point

Boiling point is the temperature at which a substance transitions from a liquid to a gas. It is influenced by molecular weight, intermolecular forces, and molecular structure. In organic compounds, stronger intermolecular forces like hydrogen bonding or dipole-dipole interactions typically result in higher boiling points.

Intermolecular Forces

Intermolecular forces are attractions between molecules, including van der Waals forces, dipole-dipole interactions, and hydrogen bonds. In hydrocarbons, van der Waals forces are predominant, and the strength of these forces increases with larger surface area and molecular weight, affecting boiling points.

Molecular Structure

Molecular structure refers to the arrangement of atoms within a molecule, impacting its physical properties. In alkanes, branching reduces surface area contact between molecules, leading to weaker van der Waals forces and lower boiling points compared to straight-chain isomers with similar molecular weights.

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List each set of compounds in order of increasing boiling point. b. Octane, (CH3)3C—C(CH3)3 and CH3CH2C(CH3)2CH2CH2CH3

Key Concepts

Boiling Point

Intermolecular Forces

Molecular Structure

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List each set of compounds in order of increasing boiling point.
b. Octane, (CH₃)₃C—C(CH₃)₃ and CH₃CH₂C(CH₃)₂CH₂CH₂CH₃