Draw the Lewis structure of the methoxide ion ( CH 3 O - ). Draw the Lewis structure of a proton (H + ) . To which atom of methoxide would you expect a proton to add?

Hello everyone. Today, we have the following problem, draw the lewis structure of the oxide ion and label the atom at which a proton is expected to be added. So the first step is to calculate the total number of valence electrons. So we are going to take the individual valence electrons of each atom and then add them up. So first, we have carbon carbon is a group four a element and therefore has four valence electrons. Since there are two of them in aide we multiply that by two to get a total of eight valence electrons moving on to hydrogen hydrogen is a group, one a element, therefore has one valance electron and there are five of them. So that's one times five, giving us five valence electrons. For hydrogen, we have oxygen that is a group six A element and therefore has six valence electrons. Since there's only one, we have six valance electrons for oxygen, now we must also add one electron for the negative charge of that oxide. And in doing so, this gives us a total of 20 valance electrons to use to construct our oxide ion. So for our leer structure, we have to keep in mind a couple of things. First, carbon prefers four bonds, oxygen prefers two bonds and hydrogen prefers one bond. So in deriving our structure, we are going to put the least electron negative atom in the center excluding hydrogen. So that would be carbon and we will place one hydrogen on that carbon. And the last bond for that carbon recall that carbon prefers four bonds will go to being added to another carbon. And so that carbon will have added either the hydrogen or oxygen, but we will add the oxygen because if we add the hydrogen, then that hydrogen would be forced to bomb with something else and that is not favorable. So the last two atoms to be added are our hydrogens onto this carbon. And so that leaves us with six electrons left over and we are going to add that to our oxygen to complete its octet. However, we also have a negative charge that we have to put on this atom on this molecule and we will put that on the oxygen. And so now we have to determine which atom will, which atom the proton is expected to be added. And so the proton is positively charged and positively charged species are attracted to negatively attracted species. So oxygen having a negative charge is most likely to gain that proton. And so we have constructed our Lewis structure and determined which atom is most likely to pick up a proton and with that, we've answered the question overall, I hope this helped. And until next time.

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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
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23. The Chemistry of Thioesters, Phophate Ester and Phosphate Anhydrides1h 10m
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33. The Organic Chemistry of Metabolic Pathways2h 52m
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36. Synthetic Polymers1h 49m

1. A Review of General Chemistry

Lewis Structure

Organic Chemistry

1. A Review of General Chemistry

Lewis Structure

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Problem 3

Textbook Question

Draw the Lewis structure of the methoxide ion ( CH₃O^-). Draw the Lewis structure of a proton (H⁺) . To which atom of methoxide would you expect a proton to add?

Verified step by step guidance

Step 1: Begin by understanding the methoxide ion (CH₃O⁻). Methoxide consists of a methyl group (CH₃) bonded to an oxygen atom. The negative charge indicates that the oxygen atom has an extra electron, making it more nucleophilic.

Step 2: Draw the Lewis structure of the methoxide ion. Represent the methyl group (CH₃) with three hydrogen atoms bonded to a central carbon atom. The carbon atom is single-bonded to the oxygen atom, which has three lone pairs of electrons and a negative charge. Use MathML to represent the structure:

{CH}_{3} - O -

Step 3: Draw the Lewis structure of a proton (H⁺). A proton is simply a hydrogen atom that has lost its electron, leaving it with a positive charge. Represent it as

H +

Step 4: Analyze the methoxide ion to determine where the proton (H⁺) would likely add. The oxygen atom in methoxide has a negative charge and lone pairs of electrons, making it highly nucleophilic and the most likely site for protonation.

Step 5: Conclude that the proton (H⁺) would add to the oxygen atom in methoxide, forming methanol (CH₃OH). This is because the oxygen atom is the most electron-rich and reactive site in the molecule.

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Key Concepts

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

Lewis Structures

Lewis structures are diagrams that represent the bonding between atoms in a molecule and the lone pairs of electrons that may exist. They use dots to represent valence electrons and lines to represent bonds. Understanding how to draw Lewis structures is essential for visualizing molecular geometry and predicting reactivity.

Methoxide Ion

The methoxide ion (CH₃O⁻) is a negatively charged species formed when methanol (CH₃OH) loses a proton (H⁺). In its Lewis structure, the oxygen atom carries a negative charge and is bonded to a carbon atom and a hydrogen atom. This ion is a strong nucleophile, meaning it readily donates its electron pair to form new bonds.

Proton Affinity

Proton affinity refers to the tendency of a molecule or ion to attract and bond with a proton (H⁺). In the case of the methoxide ion, the oxygen atom, which has a lone pair of electrons, is the most likely site for protonation due to its high electronegativity and ability to stabilize the positive charge after bonding with a proton.

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