下列表示对应化学反应的离子方程式正确的是[ ] A.FeCl3溶液与Cu的反应:

题型:选择题

问题:

下列表示对应化学反应的离子方程式正确的是[ ]

A.FeCl3溶液与C u的反应:Cu+Fe3+===Cu2++Fe2+

B.NO2与水的反应:3NO2+H2O===2NO3+NO+2H

C.醋酸溶液与水垢中的CaCO3反应:CaCO3+2H===Ca2++H2O+CO2

D.向NaAlO2溶液中通入过量CO2:2AlO2+CO2+3H2O===2Al(OH)3↓+CO32-

考点:离子方程式
题型:选择题

“重阴必阳”所体现的阴阳关系是()

A.阴阳交感

B.阴阳互根

C.阴阳对立

D.阴阳消长

E.阴阳转化

题型:选择题

如果因厂房地形的限制不能设置专用的砂轮机房,则应在砂轮机正面装设不低于( )m高度的防护挡板,并且挡板要求牢固有效。

A.1
B.1.2
C.1.8
D.2.4

题型:选择题

第一个五年计划中的重工业项目集中建设在[ ]

A.华北地区

B.西北地区

C.东北地区

D.东南地区

题型:选择题

Questions 61—65 are based on Passage Two:Passage TwoAs the 21st century begins, a number of leaders in politics, education, and other professions believe that the US must adopt some new values to go along with the old traditional ones. What new values should Americans adopt This is a very difficult question to answer. Certainly, a greater value should be placed on the conservation of natural reasources; Americans should learn to use less and waste less. But conservation has never been a p value to Americans, who have believed that their country offered an endless,abundant supply of natural resources.Recently, progress has been made—more and more Americans are recycling their paper,cans,bottles,and other goods—but old wasteful habits died hard. Furthermore,the need to protect the environment may conflict with the need for jobs,as in the Northwest ,where conservationists battle lumber companies that want to cut down ancient redwood trees. A belief in the value of conservation is still compared with other American values; it can become per only as Americans see the need for it more clearly.In addition,Americans may need to place a p value on cooperation on a national scale to achieve important national objectives. The American idea of the national good has never been based on national cooperation but rather on the freedom of the individual, maintaining those conditions that provide the greatest freedom and prosperity for the individual . It is far more difficult for Americans to accept shared sacrifice for the common good and wellbeing of the entire country. For example ,although the majority of Americans believe that it is extremely important to balance the national budget and reduce the deficit, they do not want to see cuts in government programs that benefit them personally.The American value of competition also hinders the development of a spirit of national cooperation. Competition sometimes encourages feelings of suspicion rather than the mutual trust that is necessary for successful national cooperation.Although Americans often cooperate successfully on the local level—in neighborhood groups and churches, for example, on the national level, they may see themselves as part of an interest group that is competing with other interest groups for government funds. A request by the national government for shared sacrifice may be seen as coercive and destructive rather than voluntary and constructive. However, the demands for the 21st century may compel Americans to place a greater value on national cooperation to solve problems that affect them all, directly and indirectly.

The best TITLE of this passage could be ().

A.Which is Better, New Value or Old Value

B.Conservation vs. Need for Jobs

C.The Need for New National Values

D.Cooperation and Competition

题型:选择题

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