书写规则.比如戊烷的话,先写5个c在一条直线,然后4个c一条直线,然后是三个c一条直线,多出来的c可以自己组合,再挂在刚写出来的碳链上,注意,相同的结构不能出现.
戊烷,分子式C5H12,其同分异构体有三种:
1.CH3-CH2-CH2-CH2-CH3 正戊烷
2.CH3-CH(CH3)-CH2-CH3 异戊烷(2-甲基丁烷)
3.C(CH3)4 新戊烷(2,2-二甲基丙烷)
己烷:
CH3-(CH2)4-CH3
CH3CH(CH3)-(CH2)3-CH3
CH3CH2CH(CH3)-(CH2)2-CH3
CH3CH(CH3)CH(CH3)CH2CH2CH3
CH3CH(CH3)CH2CH(CH3)CH2CH3
CH3CH(CH3)CH2CH2CH(CH3)CH3
CH3CH(CH3)CH(CH3)CH(CH3)CH3
庚烷:
CH3-(CH2)5-CH3
(CH3)2-CH-(CH2)3-CH3
CH3CH2CH(CH3)CH2CH2CH3
(CH3CH2)3CH
(CH3)3-C-CH2CH2CH3
(CH3CH2)2-C-(CH3)2
(CH3)2-CH-CH(CH3)-CH2CH3
(CH3)2-CH-CH2-CH-(CH3)2
(CH3)3-C-CH-(CH3)2