问题 选择题

1 1H、2 1H、3 1H、H+、H2是                                         (   )

A.氢的五种同位素;

B.五种氢元素;

C.氢的五种原子;

D.氢元素的五种不同微粒

答案

答案:D

题目分析:质子数相同,中子数不同的同一种元素的不同核素互称为同位素,氢气是单质分子,A、B、C不正确。所以根据微粒的组成特点可知,五种微粒应该是氢元素的五种不同微粒,D正确,答案选D。

点评:该题是基础性试题的考查,侧重对学生基础知识的巩固和训练。该题的关键是明确同位素的含义以及原子组成的表示方法,并能灵活运用即可。

阅读理解

"Indeed," George Washington wrote in his diary in 1785, "some kind of fly, or bug, had begun to eat the leaves before I left home." But the father of America was not the father of bug. When Washington wrote that, Englishmen hade been referring to insects as bugs for more than a century, and Americans had already created lightning-bug(萤火虫). But the English were soon to stop using the bugs in their language, leaving it to the Americans to call a bug a bug in the nineteenth and twentieth centuries.

  The American bug could also be a person, referring to someone who was crazy about a particular activity. Although fan became the usual term, sports fans used to be called racing bugs, baseball bugs, and the like.

  Or the bug could be a small machine or object, for example, a bug-shaped car. The bug could also be a burglar alarm, from which comes the expression to bug, that is, "to install (安装) an alarm". Now it means a small piece of equipment that people use for listening secretly to others' conversation. Since the 1840s, to bug has long meant "to cheat", and since the 1940s it has been annoying.

  We also know the bug as a flaw in a computer program or other design. That meaning dates back to the time of Thomas Edison. In 1878 he explained bugs as "little problems and difficulties" that required months of study and labor to overcome in developing a successful product. In 1889 it was recorded that Edison "had been up the two previous nights discovering 'a bug' in his invented record player."

小题1:We learn from Paragraph 1 that __________________.

A.Americans had difficulty in learning to use the word bug

B.George Washington was the first person to call an insect a bug

C.the word bug was still popularly used in English in the nineteenth century

D.both Englishman and Americans used the word bug in the eighteenth century小题2:What does the word "flaw" in the last paragraph probably mean?

A.Fault.

B.Finding.

C.Origin.

D.Explanation.小题3:The passage is mainly concerned with__________________.

A.the misunderstanding of the word bug

B.the development of the word bug

C.the public views of the word bug

D.the special characteristics of the word bug

判断题