问题 填空题

硝酸是极其重要的化工原料,工业上将产生的NO2在密闭容器中用水多次反复循环吸收制备硝酸。

(1)工业上用水吸收NO2生产HNO3,生成的气体经多次氧化、吸收的循环操作充分转化为硝酸(假定上述过程无其他损失)。试写出上述反应的化学方程式:

                                                                   

(2)为了证明NO也可以与氧气和水共同反应生成HNO3,某学生设计了如图所示装置(有关夹持装置已略去)。

①检查装置气密性良好后,为观察到NO气体生成,打开K1,关闭K2,应从U形管的长管口注入稀硝酸至     后,迅速关闭K1,观察到U形管内的现象是                                                                    

②装置Ⅲ中发生反应的化学方程式为                                   

③蘸NaOH溶液的棉花团的作用是                                     

④打开K2,至装置Ⅱ中长玻璃管中的气体呈无色后,打开K3,反应一段时间后,长玻璃管中并未充满液体。设计简单方法检验长玻璃管中的气体是否含NO                        

答案

(1)4NO2+O2+2H2O=4HNO3(或分成两个方程式写)

(2)①U形管右侧胶塞下沿 U形管左端液面高于右端,铜丝慢慢溶解,产生无色气体,溶液逐渐变蓝(至少答三点)

②2H2O22H2O+O2

③吸收氮的氧化物防止污染环境

④再打开K3,若观察到长玻璃管中气体迅速变为红棕色,则证明余气含NO,若无颜色变化,则证明不含NO(其他合理答案也可)

解答本题要注意以下两点:(1)根据实验目的和所放置的试剂确定各装置的作用。

(2)三个开关K1、K2、K3的开与关都对实验起着重要作用。

完形填空

第四部分写作(共两节,满分20分)
第一节任务型读写(共10小题;每小题1分,满分10分)
阅读下面短文,根据所读内容在表格中的空白处填入恰当的单词。注意:每个空格只填一个单词。
In a society, such as the United States or Canada, which has many national, religious and cultural differences, people highly value individualism-the difference among people. Teachers place a lot of importance on the qualities that make each student special. The educational systems in these countries show these values. Students don't memorize information. Instead, they work individually and find answers themselves. There is often discussion in the classroom. At an early age, students learn to form their own ideas and opinions.
In most Asian societies, by contrast, people have the same language, history, and culture. Perhaps for this reason, the educational system in much of the Orient reflects society’s belief in group goals and purposes rather than individualism. Children in China, Japan, and Korea often work together and help one another in assignments. In the classroom, the teaching methods are often very formal. The teacher lectures, and the students listen. There is not much discussion. Instead, the students recite rules of information that they have memorized.
There are advantages and disadvantages to both of these systems of education. For example, one advantage to the system in Japan is that there much more math and science than American students learn by the end of high school. They also study more hours each day and more days each year than North Americans do. The system is difficult, but it prepares students for a society that values discipline and self-control. There is, however, a disadvantage. Memorization is an important learning method in Japanese schools, yet many students say that after an exam, they forget much of the information that they have memorized.
The advantage of the educational system in North American, on the other hand, is that students learn to think for themselves. The system prepares them for a society that values creative ideas. There is, however, a disadvantage. When students graduate from high school, they haven’t memorized as many basic rules and facts as students in other countries have.
Title:  66  of Educational System between North America and Asia
 
Students in the US and  67  
Students in China, Japan and Korea
What do they
  68   
Individualism
    69   goals and purposes
Different
  70 of study
Working individually
Listening to the teachers
Forming their own ideas and opinions
Reciting rules and memorizing information
A lot of discussion in the classroom
Not much discussion
  71   
Learning to think for themselves
Learning much more math and science
Studying more hours each day and more days each year
Good for a society that values  72 
Good for a society valuing
  73  and self-control
Disadvantages
Students haven’t memorized many basic rules and facts before 74 
Information is  75  easily.
判断题