题干

下列说法不正确的是(  )

A:1828年贝采里乌斯的学生维勒首次在实验室里合成了尿素,取得令科学界震惊的成果

B:1965年,我国科学家首次由氨基酸合成了结晶牛胰岛素,这是第一个由全人工合成的、与天然产物性质完全相同的、具有生物活性的蛋白质

C:饱和一元醇的沸点比与其相对分子质量接近的烷烃或烯烃的沸点要高,这主要是因为氢键的存在增强了醇分子间的相互作用

D:皂化反应是指油脂在酸性条件下的水解反应

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答案(点此获取答案解析)

D

同类题1

阅读短文,从短文下面的方框中的六个句子中选择五个还原到短文中,使短文通顺完整、衔接自然。

What’s in a Name?

    Your name is very important. When you think of yourself, you probably think of your name first. ____

    Right now, the two most popular names for babies in the United States are “Jacob” for boys and “Emily” for girls. ____ And why are some name unpopular?

    Names can become popular because of famous actors, TV or book heroes, or top players. Popular names mean very positive(积极的) things. Unpopular names mean negative(消极的) things. ____ Here are some common opinions about names from a recent survey.

Boys' names                           Girls' name

George: average, boring                  Betty: old-fashioned, average

Jacob: creative, friendly                  Emily: independent, adventurous

Michael: good-looking, athletic            Jane: common, ordinary

Stanley: out of date, serious               Nicole: beautiful, intelligent

____ The biggest reason is tradition. They have no choice. Many people are named after a family member.

____ A name that is unpopular now might become popular in the future. That's good news for all the Georges and Bettys out there.

A. Chinese names are different from English names.

B. Of course, opinions can change over times.

C. Surprisingly, people usually have similar opinions about names.

D. Why are these names popular?

E. Because it is an important part of your identity (身份).

F. So why do parents give their children unpopular names?