Which is more stable, free hydrogen atoms or the diatomic H 2 molecule? Why do you know this to be true?

Welcome back, everyone justify the stability of the diatomic oxygen molecule versus free oxygen atoms. We given for answer choices. A oxygen exists only as a free oxygen atom. B, oxygen exists only as a diatomic molecule. C diatomic oxygen has greater energy than a free oxygen atom. D A free oxygen atom has higher energy than diatomic oxygen. First of all, if we locate oxygen in the periodic table, we will notice that it belongs to the group six A. And that tells us that oxygen has six valence electrons in its outer shell. If we simply draw the Louis structure, we can add four electrons in a clockwise direction. And then we will add two more, which essentially tells us that there are two unpaired electrons because oxygen has those unpaired electrons, it means that it's reactive based on the ocr according to the rule stability of an atom is achieved when an atom gains an octet or basically eight electrons in it valence shell. So oxygen has those two unpaired electrons, meaning it's highly reactive, but it can actually pair those two electrons with the other two unpaired electrons from another oxygen atom. So that both of them will achieve an octet. Let's see how that works. We're simply going to form one hava bond between two unpaired electrons and then the other one. So we are simply forming a double bond right now, if we draw the resultant structure, we get two oxygen atoms double bonded, then each auction has a long pair of electrons. And now what we simply notice is that each oxygen has eight valence electrons. We have 12345678 for the right oxygen atom. And we will notice exactly the same thing for the left one. So now each of them has that octet. And that means that atomic oxygen is much more stable compared to a free oxygen atom based on the L. So that we can say that based on our analysis, the correct choice must be b oxygen exists only as a diatomic molecule. But let's consider the other answer. Choices. A oxygen exists only as a free oxygen atom. We said that this must be not correct due to the fact that auction has unpaired electrons and it is highly reactive as a result. C the atomic oxygen has greater energy than a free oxygen atom. This is incorrect. It is actually more stable, meaning it has lower energy. Higher energy implies low stability. D A free oxygen atom has higher energy than diatomic oxygen. This is true, it does have higher energy because it is less stable as a free atom However, this statement doesn't justify the stability of the atomic oxygen versus a free oxygen atom. So even though statement D is accurate, it doesn't really support the idea that atomic oxygen is actually more stable than a free oxygen atom. So that we can conclude that our final answer is option B oxygen exists only as a diatomic molecule. 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

1. A Review of General Chemistry

Bonding Preferences

Organic Chemistry

1. A Review of General Chemistry

Bonding Preferences

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Problem 2

Textbook Question

Which is more stable, free hydrogen atoms or the diatomic H₂ molecule? Why do you know this to be true?

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Understand the question: The problem is asking about the relative stability of free hydrogen atoms (H) versus the diatomic hydrogen molecule (H₂). Stability in this context is related to energy—lower energy corresponds to greater stability.

Recall the concept of bond formation: When two hydrogen atoms combine to form an H₂ molecule, they form a covalent bond by sharing their electrons. Bond formation releases energy, which means the system moves to a lower energy state.

Apply the principle of energy minimization: The H₂ molecule is more stable than free hydrogen atoms because the energy released during bond formation makes the molecule lower in energy compared to the separate atoms.

Consider experimental evidence: The bond dissociation energy of H₂ (the energy required to break the H-H bond) is a positive value, indicating that energy must be supplied to break the bond and separate the molecule into free hydrogen atoms. This further supports that H₂ is more stable.

Conclude based on thermodynamics: The diatomic H₂ molecule is more stable than free hydrogen atoms because the formation of the H-H bond lowers the system's energy, and systems naturally favor lower-energy, more stable configurations.

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Key Concepts

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

Bond Formation and Stability

The stability of a molecule is often determined by the presence of chemical bonds. In the case of diatomic hydrogen (H₂), two hydrogen atoms share a pair of electrons, forming a covalent bond. This bond lowers the energy of the system compared to free hydrogen atoms, which exist as individual, unbonded entities. Thus, the formation of H₂ results in a more stable configuration.

Energy Considerations

Chemical stability is closely related to energy levels. Free hydrogen atoms have higher potential energy due to their unbonded state. When they form H₂, energy is released, indicating that the H₂ molecule is at a lower energy state. This release of energy during bond formation is a key factor in determining the stability of molecules.

Thermodynamics and Reaction Favorability

Thermodynamics helps explain why certain reactions occur spontaneously. The formation of H₂ from free hydrogen atoms is favored because it leads to a decrease in Gibbs free energy, making the process thermodynamically favorable. This principle underlines the preference for stable molecular forms over individual atoms in chemical systems.

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