甲 、乙、丙、丁、戊均为中学化学常见的单质或化合物,且均含有同一种元素R,在一定

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问题:

甲 、乙、丙、丁、戊均为中学化学常见的单质或化合物,且均含有同一种元素R,在一定条件下其转化关系如右图所示。

(1)若R为一种非金属元素,且上述五种物质含有不同的官能团,丁为带水果香味的液体,乙和丁均能在碱性条件下生成甲,戊是一种无色气体,相同条件下相对H2的密度为14,则由甲在一定条件下生成戊的化学方程式为                ,欲检验乙中官能团,所选用的试剂为(填序号)                        

①  NaOH溶液  ② Br2的CCl4溶液   ③银氨溶液   ④ AgNO3溶液  ⑤ 稀HNO3

(2)若R为另一种非金属元素,甲与丙为常见大气污染物,且甲与丙的相对分子质量相差16。乙在常温下为气体,丁为空气的主要成分之一。则丁的电子式为              ,乙的空间构型为             ;戊的稀溶液能跟过量铁粉反应,其离子方程式为               

(3)若R为一种金属元素,乙由两种元素组成,甲溶液的pH小于7,单质丁在一定条件下可生成戊。甲与戊两种溶液混合生成沉淀丙的离子方程式为                      ,除去镁粉中混有少量的丁,涉及的离子方程式为                                   

考点:芳香烃的通式卤代烃苯的同系物
题型:填空题
如图所示,理想变压器的原副线圈匝数比n1:n2=1:10,副线圈与阻值R=20Ω的电阻相连.原线圈两端所加的电压u=20sin20πt(V),则(  )

A.副线圈输出交流电的频率为10Hz

B.交流电压表的示数为20V

C.电阻R上消耗的电功率为2kW

D.原线圈中电流的最大值为100A

题型:填空题

D

Recently there was a major discovery in the scientific research—the mapping of all DNA in a human gene(基因) is complete.Couple of years ago, this seems an impossible task for scientist to accomplish.All this progress in science leads us to believe that the day, when the human being will be cloned, is not far away.Human cloning has always been a topic of argument, in terms of morality or religion.

Taking a look at why cloning might be beneficial, among many cases, it is arguable that parents who are known to be at risk of passing a genetic limitation to a child could make use of cloning.If the clone was free of genetic limitations.then the other clone would be as well.The latter could foe inserted in the woman and allowed to ripen to term.Moreover, cloning would enable women, who can't get pregnant, to have children of their own.

Cloning humans would also mean that organs could be cloned, so it would be a source of perfect transfer organs.This, surely would be greatly beneficial to millions of unfortunate people around the world that are expected to lose their lives due to failure of single (or more) organ (s).It is also arguable that a ban on cloning may be unlawful and would rob people of the right to reproduce and limit the freedom of scientists.

Arguments against cloning are also on a perfectly practical side.Primarily, I believe that cloning would step in the normal "cycle" of life.There would be a large number of same genes, which reduce the chances of improvement, and, in turn, development—the fundamental reason how living things naturally adapt to the ever-changing environment.Life processes failing to do so might result in untimely disappearance.Furthermore, cloning would make the uniqueness that each one of us possesses disappear.Thus, leading to creation of genetically engineered groups of people for specific purposes and, chances are, that those individuals would be regarded as "objects" rather than people in the society.

Scientists haven't 100 per cent.guaranteed that the first cloned humans will be normal.Thus this could result in introduction of additional limitations in the human "gene-pool".

Regarding such arguable topics in "black or white" approach seems very innocent to me personally.We should rather try to look at all "shades" of it.I believe that cloning is only legal if its purpose is for cloning organs; not humans.Then we could regard this as for "saving life" instead of "creating life".I believe cloning humans is morally and socially unacceptable.

67.Which of the following is true according to the passage?

A.Genetic limitation will be beneficial for some women.

B.A large number of genes will prevent us from developing.         

C.Prohibition of cloning might limit the freedom of scientists.

D.First cloned humans might be normal according to scientists.

68.What's the author's opinion on cloning?

A.Cloning should be entirely banned.

B.Cloning should be used in creating life.

C.Cloning will take away the right to reproduce.

D.Cloning is acceptable if it is used for cloning organs.

69.Where can you read this article?

A.In a story book.        

B.In a magazine.

C.In a science fiction.   

D.In a brochure.

70.Which of the following shows the structure of the passage?

题型:填空题
如图所示,在x轴上方存在着垂直于纸面向里、磁感应强度为B的匀强磁场,一个不计重力的带电粒子从坐标原点O处以速度v进入磁场,粒子进人磁场时的速度方向垂直于磁场且与x轴正方向成120°角,若粒子穿过y轴正半轴后在磁场中到x轴的最大距离为a,则该粒子的比荷和所带电荷的正负是(  )

A.,正电荷

B.,正电荷

C.,负电荷

D.,负电荷

题型:填空题

有抗疟作用的化学成分是()

A.青蒿素

B.京尼平苷

C.鱼腥草素

D.苦参碱

E.小檗碱

题型:填空题

“启蒙”多指我们的内心世界,而不是外部世界。

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