问题 问答题

水的蒸发和氧化汞分解有什么不同?(用分子、原子的观点解释)

(1)水的蒸发:______;

(2)氧化汞受热分______.

答案

(1)水的蒸发是指水由液态变为气态,是分子之间的间隔变大;

(2)根据分子的定义可以知道分子是保持化学性质的最小微粒,所以在化学变化中分子破裂成原子,原子重新组合成新的物质的分子,所以氧化汞受热变成了汞和氧气,该变化过程中:氧化汞分子受热变成氧原子和汞原子,每2个氧原子构成1个氧分子,大量氧分子构成氧气,大量汞原子直接构成金属汞.

故答案为:(1)水由液态变为气态,是分子之间的间隔变大;

(2)氧化汞分子受热变成氧原子和汞原子,每2个氧原子构成1个氧分子,大量氧分子构成氧气,大量汞原子直接构成金属汞.

阅读理解

阅读理解。

     If you haven't heard or seen anything about Road Rage in the last few months, you've probably been

avoiding the media. There have been countless stories about this new and scary phenomenon, considered

a type of aggressive driving. You have most likely encountered aggressive driving or

Road Rage recently if you drive at all.  

     While drunk driving remains a critical problem, the facts about aggressive driving are surely as

disturbing. For instance, according to the National Highway Transportation Safety Association, 41,907

people died on the highway last year. Of those deaths, the agency estimates that  about two-thirds were

caused at least in part by aggressive driving behavior.

     Why is this phenomenon occurring more than ever now, and why is it something that seemed

almost nonexistent a few short years ago? Experts have several theories, and all are probably

partially correct. One suggestion is sheer overcrowding. In the last decade, the number of cars on

theroads has increased by more than 11 percent, and the number of miles driven has increased by 35

percent. However, the number of new road miles has only increased by 1 percent. That means more cars

in the same amount of space; and the problem is magnified in urban areas. Also, people have less time

and more things to do. With people working and trying to fit extra chores and activities into the day,

stress levels have never been higher. Stress creates anxiety, which leads to short tempers. These factors,

when combined in certain situations, can spell Road Rage.

     You may think you are the last person who would drive aggressively, but you might be

surprised. For instance, have you ever yelled out loud at a slower driver, sounded the horn long

and hard at another car, or sped up to keep another driver from passing? If you recognize yourself in any

of these situations, watch out!

     Whether you are getting angry at other drivers, or another driver is visibly upset with you,  there are

things you can do to avoid any major conflict. If you are susceptible(easily influenced) to Road Rage, the

key is to discharge your emotion in a healthy way. If you are the  target of another driver's rage, do

everything possible to get away from the other driver safely,  including avoiding eye contact and getting

out of their way.    

1. The first sentence in Para. 1 implies that ______.  

A. one may be angered by media reports and wants to avoid them

B. the media coined the term "Road Rage" only a few months ago

C. Road Rage has received much media coverage in the last few months

D. people not interested in the media know little about recent

happenings

2. The underlined word "spell" in Para. 3 means ________.  

A. relieve             

B. cause          

C. spread            

D. prevent

3. Which of the following characterizes aggressive driving?   

A. Talking while driving.              

B. Driving at high speed. 

C. Sounding the horn when passing.      

D. Shouting at another driver.

4. The last paragraph is intended to _________.   

A. tell people how to deal with Road Rage 

B. inform people how aggressive drivers could be 

C. show people how to control themselves when angry 

D. warn people against eye contact with another driver

单项选择题