Skip to main content
Ch. 5 - Chemical Reaction Analysis: Thermodynamics and Kinetics
Mullins - Organic Chemistry: A Learner Centered Approach 1st Edition
Mullins1st EditionOrganic Chemistry: A Learner Centered ApproachISBN: 9780137566471당신이 사용하는 게 아니라요?교과서 변경
모든 교과서Mullins 1st EditionCh. 5 - Chemical Reaction Analysis: Thermodynamics and Kinetics문제 3a
4장, 문제 3a

Which is the most stable base in each pair?
(a)

검증된 단계별 안내
1
Step 1: Analyze the chemical structures provided in the image. The first structure is a deprotonated ketone (a carbonyl group with a negative charge on the carbon atom), while the second structure is a deprotonated carboxylic acid (a carbonyl group with a negative charge on the oxygen atom).
Step 2: Recall that the stability of a base is influenced by the ability of the molecule to delocalize or stabilize the negative charge. Resonance and electronegativity play key roles in this stabilization.
Step 3: Evaluate the resonance possibilities for each structure. In the deprotonated carboxylic acid, the negative charge on the oxygen atom can be delocalized through resonance with the adjacent carbonyl group, making it more stable. In contrast, the negative charge on the carbon atom in the deprotonated ketone has limited resonance stabilization.
Step 4: Consider electronegativity. Oxygen is more electronegative than carbon, meaning it is better able to stabilize a negative charge. This further contributes to the stability of the deprotonated carboxylic acid compared to the deprotonated ketone.
Step 5: Conclude that the deprotonated carboxylic acid (the structure with the negative charge on the oxygen atom) is the more stable base in this pair due to resonance stabilization and the electronegativity of oxygen.

비슷한 문제에 대한 검증된 영상 답변:

이 영상 해법은 위 문제에 도움이 된다고 튜터들이 추천한 것입니다.
영상 길이:
2m

주요 개념

질문에 올바르게 답하기 위해 반드시 이해해야 하는 핵심 개념들은 다음과 같습니다.

Acidity and Basicity

In organic chemistry, acidity refers to the tendency of a compound to donate a proton (H+), while basicity is the ability to accept a proton. The stability of a base is often inversely related to the acidity of its conjugate acid. Understanding the relationship between acids and bases is crucial for determining which species is more stable in a given pair.
추천 영상:
06:21
Understanding the difference between basicity and nucleophilicity.

Resonance Stabilization

Resonance stabilization occurs when a molecule can be represented by two or more valid Lewis structures, allowing the electron density to be delocalized. This delocalization lowers the energy of the molecule, making it more stable. In the context of the question, the presence of resonance in one of the bases can significantly influence its stability compared to the other.
추천 영상:
03:43
The radical stability trend.

Electronegativity and Charge Distribution

Electronegativity is the tendency of an atom to attract electrons towards itself. In the context of charged species, the stability of a base can be affected by the electronegativity of the atom bearing the charge. A more electronegative atom can better stabilize a negative charge, leading to a more stable base. This concept is essential for comparing the stability of the bases shown in the image.
추천 영상:
1:47
Electronegativity
관련 실천
교과서 질문

Predict which side of the equilibrium is favored for each of the chair–chair interconversions (ring flips) shown.

(a)

1299
views
교과서 질문

Which is the most acidic compound in each pair?

(a)

1482
views
교과서 질문

Which is the most stable base in each pair?

(b) HS– and HO–

1273
views
교과서 질문

(ii) Which side of the reaction is favored by entropy? (iii) If ∆S° = 0 for these reactions, calculate ∆G° (Assume T = 298 K) [BDE for O―H = 110 kcal /mol.]

(b)

1261
views
교과서 질문

Predict which side of the equilibrium is favored for each of the chair–chair interconversions (ring flips) shown.

(c)

1064
views
교과서 질문

Which is the most stable base in each pair?

(c) NH3 vs. H2O

1136
views