分子式为C4H9Cl的同分异构体有
A. 2种
B. 3种
C. 4种
D. 5种
E. 6种
苯乙烯中存在
A. p-π共轭
B. π-π共轭
C. σ-π超共轭
D. sp杂化
E. sp3杂化
下列化合物发生SN1反应的速度快慢顺序为 ①氯代环己烷 ②1-甲基-1-氯环己烷 ③氯甲基环己烷
A. ①＞②＞③
B. ②＞①＞③
C. ③＞①＞②
D. ③＞②＞①
E. ①＞③＞②
The stress in-teen numbers moves to the first syllable when___________ (choose all that are true)
A. it is part of a year.
B. counting.
C. it is followed by a stressed syllable.
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