(1)该烷烃主链最长的碳链含有6个C,称为己烷;编号从左边开始,取代基编号最小,在2号C和4号C上各有一个甲基,该有机物命名为:2,4二甲基己烷,
故答案为:2,4二甲基己烷;
(2)该结构简式属于键线式,该烷烃主链最长的碳链含有6个C,称为己烷;编号从左边开始,取代基编号最小,在2号C和4号C上各有2个甲基,5号C上各有1个甲基,3号位上2个乙基,该有机物命名为:2,2,4,4,5-五甲基-3,3-二乙基己烷,故答案为:2,2,4,4,5-五甲基-3,3-二乙基己烷;
(3)1,2-二甲基-3-乙基苯的结构简式为:
![](https://video.ask-data.xyz/img.php?b=https://iknow-pic.cdn.bcebos.com/38dbb6fd5266d01651252999942bd40735fa3546?x-bce-process=image%2Fresize%2Cm_lfit%2Cw_600%2Ch_800%2Climit_1%2Fquality%2Cq_85%2Fformat%2Cf_auto)
,故答案为:
![](https://video.ask-data.xyz/img.php?b=https://iknow-pic.cdn.bcebos.com/38dbb6fd5266d01651252999942bd40735fa3546?x-bce-process=image%2Fresize%2Cm_lfit%2Cw_600%2Ch_800%2Climit_1%2Fquality%2Cq_85%2Fformat%2Cf_auto)
.