객관식
Which of the following best describes the polarity of (sulfur difluoride)?
93
views
2. Molecular Representations
Functional Groups
객관식
Which of the following correctly ranks the substituents nitro (), methyl (), and methoxy () on a benzene ring in order of increasing electron-donating ability?
A
Nitro Methoxy Methyl
B
Methoxy Methyl Nitro
C
Nitro Methyl Methoxy
D
Methyl Nitro Methoxy
검증된 단계별 안내1
Step 1: Understand the nature of each substituent on the benzene ring in terms of their electron-donating or electron-withdrawing effects. The nitro group (\( \mathrm{NO_2} \)) is a strong electron-withdrawing group due to its resonance and inductive effects, the methyl group (\( \mathrm{CH_3} \)) is a weak electron-donating group through hyperconjugation, and the methoxy group (\( \mathrm{OCH_3} \)) is a strong electron-donating group due to resonance donation of lone pairs on oxygen.
Step 2: Recall that electron-withdrawing groups decrease electron density on the benzene ring, while electron-donating groups increase it. Therefore, the nitro group will have the least electron-donating ability (actually electron-withdrawing), methyl will have moderate electron-donating ability, and methoxy will have the highest electron-donating ability.
Step 3: Rank the substituents from least to greatest electron-donating ability based on their electronic effects: nitro (strongly withdrawing) < methyl (weakly donating) < methoxy (strongly donating).
Step 4: Express this ranking using the inequality notation: \( \mathrm{NO_2} < \mathrm{CH_3} < \mathrm{OCH_3} \), where the symbol \( < \) means 'less electron-donating than'.
Step 5: Confirm that this order matches the known chemical behavior of these substituents on aromatic rings, which is important for predicting reactivity and directing effects in electrophilic aromatic substitution reactions.
관련 영상
관련 실천
