问题 填空题

下图表示某些物质间转化关系.其中A、D是由相同元素组成的固体,且A为紫黑色,C为黑色粉末,B、E为常见气体;X与F是由相同元素组成的无色液体,且X具有消毒杀菌作用;Y是一种红色金属.请回答下列问题:

(1)A的化学式是______;

(2)C物质在反应③中的作用______;

(3)写出反应②、④、⑥的化学方程式:

②______;

④______;

⑥______;

(4)若将合成气中两气体按分子数之比为1:1进行化合(原子利用率为100%),可合成多种有机化工产品,写出其中一种可能产品的化学式______.

答案

(1)B和甲烷能够点燃,所以B就是氧气,且A为紫黑色,C为黑色粉末,A、D是由相同元素组成的固体,所以A就是高锰酸钾,C就是二氧化锰,D就是锰酸钾,Y是一种红色金属,所以Y就是铜,X与F是由相同元素组成的无色液体,且X具有消毒杀菌作用,二氧化锰和X会生成氧气,所以X就是过氧化氢,F就是水,E就是二氧化碳,绿色固体就是碱式碳酸铜,故答案为:KMnO4

(2)二氧化锰可以加快过氧化氢的分解速率,而本身的质量和化学性质都没有变,满足催化剂的定义,故答案为:催化剂或催化作用,

(3)②甲烷和氧气在点燃的条件下生成水和二氧化碳,故答案为:CH4+2O2

 点燃 
.
 
CO2+2H2O

④铜和二氧化碳、水和氧气反应生成碱式碳酸铜,故答案为:2Cu+O2+H2O+CO2=Cu2(OH)2CO3

⑥一氧化碳和氧化铁在高温的条件下生成铁和二氧化碳,故答案为:Fe2O3+3CO

 高温 
.
 
2Fe+3CO2

(4)反应的生成物只要满足C、H、O原子个数比是1:2:1即可,故答案为:CH2O或C2H4O2、C3H6O3、C4H8O4、C6H12O6

阅读理解

For high school leavers starting out in the working world,it is very important to learn particular skills and practice how to behave in an interview or how to find all internship(实习).In some countries,schools have programs to help students onto the path to work.In the Unites States,however,such programs are still few and far between.

Research shows that if high schools provide career-related courses,students are likely to get higher earnings in later years.The students are more likely to stay in school,graduate and go on to higher education.

In Germany,students as young as 13 and 14 are expected to do internships.German companies work with schools to make sure that young people get the education they need for future employment.

But in America, education reform programs focus on how well students do in exams instead of bringing them into contact with the working world.Harvard Education school professor Robert Schwartz has criticized education reformers for trying to place all graduates directly on the four-year college track.Schwartz argued that this approach leaves the country’s most vulnerable(易受影响的)kids with no jobs and no skills.

Schwartz believed that the best career programs encourage kids to go for higher education while also teaching them valuable practical skills at high school.James Madison High School in New York,for example,encourages students to choose classes on career—based courses.The school then helps them gain on—the-job experience in those fields while they’re still at high school.

However,even for teens whose schools encourage them to connect with work,the job market is daunting.In the US,unemployment rates for 16-to 19-year-olds are above 20 percent for the third summer in a row.

“The risk is that if teenagers miss out on the Summer job experience,they become part of this generation of teens who had trouble in landing a job,”said Michael,a researcher in the US.

小题1:In the author’s opinion, American high school leavers__________.

A.have enough career-related courses

B.need more career advice from their schools

C.perform better in exams than German students

D.can get higher earnings in later years小题2:According to Robert Schwartz,_________.

A.there is no need for kids to go for higher education in the US

B.students should get contact with the working world at high school

C.education reform should focus on students’ performance in exams

D.teenagers in the US can’t miss out on the summer job experience小题3:What can be inferred from the text?

A.Unemployment rates for US teenagers remain high at the moment.

B.Students with career—based courses never have problems finding a job.

C.US companies work with schools to prepare young people for future employment.

D.High school leavers with no practical skills can’t find a job absolutely小题4:What’s the main idea of the text?

A.Arguments about recent US education reform.

B.Tips on finding jobs for high school leavers.

C.The lack of career—based courses in US high schools.

D.Advice for American high school leavers.小题5:The underlined word “daunting” in Paragraph 6 most probably means___________.

A.discouraging

B.interesting

C.creative

D.unbearable

问答题 简答题