In Chapter 4, we explain that molecules like CH 3 - are Lewis bases or electron pair donors. What makes it a Lewis base?

All right. Hi everyone. So this question is asking us to explain briefly what makes the ions like H 21 negative a low space. Here we have four different choices labeled a through D proposing different possible explanations. Now, it's worth mentioning that all of them discuss attempting to achieve relative stability. And these explanations include a double bond loan pairs of electrons excess hydrogens or an empty P orbital. So first, let's go ahead and start with the Leis acid based definition. Recall that a Luis acid base reaction involves the transfer of an electron pair as opposed to a proton. So a Luis acid is the species that is going to accept a lone pair of electrons where is a Louis peace is a species that is going to donate said electron per. So Luis Acid is a chemical compound capable of accepting an extra electron pair. These include, for example, hydrogen atoms connecting to electron elements, positively charged metal ions and compounds whose central element contains less than eight valence electrons. Now, on the other hand, a Lewis base is any compound that is said to be electron rich. In other words, compounds that have lone pairs on elements like oxygen or nitrogen and anions are those with a negative charge. And so when examining the given we have H two and negative. Now, here we have the nitrogen in the center with two hydrogens connecting to it. But the reason why nitrogen has a negative charge is because of the two lone pairs present on it. So the presence of the lone pairs on this nitrogen atom are what allow it to donate electrons and behave as Lewis base. Now on, on the topic of stability, specifically, recall it, a charge species is considered to be generally less stable than its neutral counterpart. And so the extra amount of electrons on nitrogen that causes the negative charge causes stability or instability, I should say within the ion. So there's extra incentive for nitrogen to donate those extra electrons as a means of achieving neutrality and therefore relative stability. So there you have it, with that being said, our answer is going to be option B in the multiple choice because H 21 negative has two lone pairs in the central atom that allow it to donate electrons to achieve relative stability. So there you have it. And 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

3. Acids and Bases

Acids and Bases

Organic Chemistry

3. Acids and Bases

Acids and Bases

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Problem 86

Textbook Question

In Chapter 4, we explain that molecules like CH₃^- are Lewis bases or electron pair donors. What makes it a Lewis base?

Verified step by step guidance

Understand the concept of a Lewis base: A Lewis base is a species that donates an electron pair to form a covalent bond. This is a fundamental concept in acid-base chemistry.

Analyze the structure of CH₃⁻: The methyl anion (CH₃⁻) consists of a carbon atom bonded to three hydrogen atoms, with a lone pair of electrons on the carbon atom. This lone pair is key to its behavior as a Lewis base.

Identify the electron pair donor: The lone pair of electrons on the carbon atom in CH₃⁻ is available for donation. This makes CH₃⁻ capable of acting as a Lewis base by donating this electron pair to an electron-deficient species (a Lewis acid).

Relate to electron density: The negative charge on CH₃⁻ increases the electron density around the carbon atom, enhancing its ability to donate the lone pair of electrons. This is why CH₃⁻ is a strong Lewis base.

Connect to Chapter 4: In Chapter 4, you will explore more examples of Lewis bases and their interactions with Lewis acids, as well as the role of electron pair donation in forming covalent bonds.

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Key Concepts

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

Lewis Acid-Base Theory

The Lewis acid-base theory expands the definition of acids and bases beyond the Brønsted-Lowry theory. In this framework, a Lewis acid is an electron pair acceptor, while a Lewis base is an electron pair donor. This theory is crucial for understanding how molecules interact in terms of electron transfer, which is fundamental in organic chemistry.

Electron Pair Donation

Electron pair donation refers to the ability of a molecule to provide a pair of electrons to another molecule or ion during a chemical reaction. In the case of CH₃⁻, the negative charge indicates an excess of electrons, allowing it to act as a Lewis base by donating its lone pair to a Lewis acid, facilitating bond formation.

Molecular Structure and Charge

The molecular structure and charge of a compound significantly influence its reactivity and classification as a Lewis base. For CH₃⁻, the presence of a negative charge indicates a high electron density, making it more likely to donate electrons. Understanding how molecular geometry and charge distribution affect electron availability is essential for predicting chemical behavior.

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