试题与答案

A、B、D、E、F、G为短周期元素,且原子序数依次递增。A、F同主族,E、G同主

题型:填空题

题目:

A、B、D、E、F、G为短周期元素,且原子序数依次递增。A、F同主族,E、G同主族。A与其他非金属元素化合时易形成共价键,F与其他非金属元素化合时易形成离子键,且F与E2核外电子排布相同,B是形成化合物种类最多的元素。

请回答以下问题:

(1)G在周期表的位置               

(2)写出D元素单质的电子式            

(3)E、F形成的既有离子键又有共价键的化合物与A2E反应的方程式                

(4)B、D、E氢化物的稳定性从大到小的顺序(用化学式表示,下同):                   

E、G所在主族最高价氧化物对应水化物酸性最强的是            ,某种金属与其浓溶液在加热条件下可以得到一种蓝色溶液,用惰性电极电解该溶液时,阳极的电极反应式______________________;

(5)由A、B组成的化合物中,含A量最高的物质的化学式是                

答案:

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题型:阅读理解

Standardized exam in American public education are being reformed. Over the next four years, hundreds of university professors and testing experts will work together to design new assessment system.

The new tests will be computer-based and will measure higher-order skills ignored by the multiple-choice exams used in all states,including students’ ability to read complex texts, synthesize(合成)information and do research projects.

Because the new tests will be computerized and will be administered several times throughout the school year, they can provide faster feedback(反馈)to teachers.If these plans work out, It’ll turn the current testing system upside down.

One group,led by Florida,will be made up of 25 states and the District of Columbia.The group was awarded $170 million.The other group, whose membership over-laps the first,has31 states and is led by Washington.The group was given $160 million.Twelve of the 44 states are

participating in both groups but are expected eventually to choose one set of tests.

The two groups are supposed to work in a friendly competition,though their plans are very similar.Both groups will produce tests that rely heavily on technology and both groups’ tests will include so-called performance-based tasks,designed to mirror complex,real-world situations.

In performance-based tasks,students are given a problem-they could be told, for example, to suppose they are a mayor who needs to reduce a city’s pollution—and must write about how they would solve the problem.

The new tests could be useful to teachers by giving them information on what their students are learning, but it might also require some mid-course adjustments.

Over the past decade, the federal No Child Left Behind law has emphasized helping low-achieving students improve their basic reading and math by encouraging states to produce tests that measure relatively low-1evel skills. Although the Bush-era law is still on the books, two

years of Obama administration policy have been leading schools in new directions.   

小题1:. . What is the main idea of this passage?

A.Obama’s education policy takes the lead.

B.A computer-based testing system is adopted.

C.American education system has been changed.

D.Experts are reinventing the student testing system.小题2:.  Why are multiple-choice exams to be given up?

A.Because they are not computer-based.

B.Because they can’t test students’ higher-order skills.

C.Because they can’t provide proper feedback for teachers.

D.Because they can’t test students’ general reading ability.小题3:.  The underlined part in Para. 4 probably means________.

A.the two groups have some shared members

B.the other group is more demanding than the first

C.the groups have different tasks of their own

D.the other group does better than the first group in the task小题4:.  According to the passage, performance-based tasks may refer to tasks that______.

A.are related to real-world problems

B.have to be performed in an imaginary world

C.teach us theories through complex problems

D.can only be completed by relying heavily on technology小题5:. . From the last paragraph, we can infer that_________.

A.the No child Left Behind policy is not helpful

B.the Obama administration’s policy is highly praised

C.the two policies both emphasize math and reading abilities

D.the two policies both emphasize the development of practical skills

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