Question

Rank the following carbonyl compounds in order of increasing equilibrium constant for hydration: CH3COCH2Cl ClCH2CHO CH2O CH3COCH3 CH3CHO

Accepted Answer

Step 1: Understand the hydration equilibrium constant. The equilibrium constant for hydration of carbonyl compounds depends on the electrophilicity of the carbonyl carbon. Electrophilicity is influenced by the substituents attached to the carbonyl group and their ability to stabilize or destabilize the partial positive charge on the carbonyl carbon. Step 2: Analyze the substituents on each compound. Electron-withdrawing groups (like Cl) increase the electrophilicity of the carbonyl carbon, making hydration more favorable. Conversely, electron-donating groups (like alkyl groups) decrease electrophilicity, making hydration less favorable. Step 3: Rank the compounds based on substituents: 
- CH2O (formaldehyde) has no substituents, making its carbonyl carbon highly electrophilic.
- ClCH2CHO has one electron-withdrawing chlorine atom, increasing electrophilicity.
- CH3CHO (acetaldehyde) has one electron-donating methyl group, decreasing electrophilicity.
- CH3COCH2Cl has a chlorine atom further away from the carbonyl group, reducing its effect compared to ClCH2CHO.
- CH3COCH3 (acetone) has two electron-donating methyl groups, making its carbonyl carbon the least electrophilic. Step 4: Consider steric effects. Steric hindrance can also affect hydration. Smaller molecules like CH2O and ClCH2CHO are less sterically hindered, making hydration easier compared to larger molecules like CH3COCH3. Step 5: Final ranking based on increasing equilibrium constant for hydration: CH3COCH3 \u003c CH3COCH2Cl \u003c CH3CHO \u003c ClCH2CHO \u003c CH2O.

Rank the following carbonyl compounds in order of increasing equilibrium constant for hydration:
CH₃COCH₂Cl ClCH₂CHO CH₂O CH₃COCH₃ CH₃CHO

비슷한 문제에 대한 검증된 영상 답변:

주요 개념

Carbonyl Compounds

Hydration Equilibrium

Electronic and Steric Effects