题干

分析推理是化学学习过程中的常用方法,下列推理正确的是(   )

A:物质和氧气发生的反应是氧化反应,所以发生氧化反应一定有氧气参加

B:分子、原子可以构成物质,所以物质一定是由分子、原子构成的

C:可燃物燃烧时温度需要达到着火点,所以可燃物的温度达到着火点一定能燃烧

D:化合物是含有不同元素的纯净物,所以含有不同种元素的纯净物一定是化合物

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答案(点此获取答案解析)

D

同类题3

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Stanley: out of date, serious               Nicole: beautiful, intelligent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