搜题请搜索小程序“爱下问搜题”
问题 选择题

将1-氯丙烷跟NaOH的醇溶液共热，生成的产物再跟溴水反应，得到一种有机物，它的同分异构体有（除它之外）（　　）

A．2种

B．3种

C．4种

D．5种

答案

在NaOH的醇溶液中，1氯丙烷发生消去反应生成丙烯CH2═CHCH3，丙

烯加溴后，生成1，2二溴丙烷，即CH2Br-CHBr-CH3，它的同分异构体有

，共3种，

故选B．

单项选择题

胰岛素分泌不足可导致

A．呆小症

B．侏儒症

C．巨人症

D．肢端肥大症

E．糖尿病
查看答案
单项选择题

"Culture shock" occurs as a result of total immersion in new culture. It (51) to "people who have been suddenly transplanted abroad. " Newcomers may be anxious (52) they do not speak the language, know the (53) , or understand people’s behavior in daily life. The visitor finds that "yes" may not always mean "yes", that friendliness does not (54) mean friendship or that statements that appear to be serious are really intended (55) jokes. The foreigner may be unsure as to when to shake hands or embrace, when to (56) conversations, or how to approach a stranger. The (57) . of "culture shock" helps explain feelings of bewilderment and disorientation. Language problems do not account for all the frustrations that people feel. When one is (58) of everything that was once familiar, such as understanding a transportation system, knowing how to register for university classes, (59) knowing how to make friends, difficulties in coping with the new society may (60) .

52（）。

A. so that

B. because

C. unless

D. though
查看答案