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已知：A、B为常见的非金属单质且均为气体；甲、乙为金属单质，乙在I的浓溶液中发生钝化；C、H、J的溶液均呈碱性．各物质间的转化关系如下（部分生成物未给出，且未注明反应条件）：

（1）写出反应②的化学方程式______

（2）反应④中每消耗1mol G，转移电子的物质的量为______．

（3）反应⑥的离子方程式是______．

（4）实验室中保存I的方法是______．

答案

A、B为常见的非金属单质且均为气体；甲、乙为金属单质，乙在I的浓溶液中发生钝化；C、H、J的溶液均呈碱性，则C为NH3，D为NO，G为NO2，反应④为G与水的反应，I为硝酸；结合转化及溶液的碱性，则甲为Na，E为水，H为NaOH，乙为Al，反应⑥为Al与NaOH溶液反应，则J为NaAlO2，A为H2，所以B为氮气，

（1）反应②的化学方程式为4NH3+5O2

 催化剂 
.
 
4NO+6H2O，故答案为：4NH3+5O2
 催化剂 
.
 
4NO+6H2O；

（2）由3NO2+H2O═HNO3+NO可知，3molG参加反应转移2mol电子，则每消耗1molG，转移电子的物质的量为

2
3
mol，

故答案为：

2
3
；

（3）反应⑥的离子方程式为2Al+2H2O+2OH-═2AlO2-+3H2↑，故答案为：2Al+2H2O+2OH-═2AlO2-+3H2↑；

（4）I为硝酸，见光易分解，则保存在棕色试剂瓶中，放在阴凉处，故答案为：保存在棕色试剂瓶中，放在阴凉处．

问答题

Passage 2
My wife Nane and I are both extremely happy to be with you today. I feel truly proud to belong to this extraordinary class of 2004, and I am pleased to see that so many parents and family members were here today. The day belongs to them, too. Without their constant support, understanding and sacrifice, none of us could have achieved what we have. For me, to receive a degree from Harvard is a very great honor indeed. There are few countries in the world whose leaders in public life, business, science and the humanities have not had some association with Harvard -- and no country that has not benefited from Harvard’s outstanding contributions to human knowledge.//
You have invited me, I know, not as an individual, but as Secretary-General of the United Nations. You are saying that the United Nations matters, and that you want to hear what we have to say. Are you right in believing that the UN matters I think you are, because the UN offers the best hope of a stable world and a broadly equitable world order, based on generally accepted roles. That statement has been much questioned in the past year. But recent events have reaffirmed, and even strengthened, its validity. A role-based system is in the interest of all countries --especially today. Globalization has shrunk the world. The very openness, which is such an important feature of today’s most successful societies, makes deadly weapons relatively easy to obtain, and terrorists relatively difficult to restrain. //
Today, the p feel almost as vulnerable to the weak as the weak feel vulnerable to the p. So it is in the interest of every country to have international rules and to abide by them. And such a system can only work if, in devising and applying the rules, the legitimate interests of all countries are accommodated, and decisions are reached collectively. That is the essence of multilateralism, and the founding principle of the United Nations. All great American leaders have understood this. That is one of the things that make this country such a unique world power. America feels the need to frame its policies, and exercise its leadership, not just in the light of its own particular interests, but also with an eye to international interests, and universal principles.//
Among the finest examples of this was the plan for reconstructing Europe after World War Ⅱ, which General Marshall announced here at Harvard in 1947. That was one part of a larger-scale and truly statesmanlike effort, in which Americans joined with others to build a new international system -- a system which worked, by and large, and which survives, in its essentials, nearly 60 years later. During those 60 years, the United States and its partners developed the United Nations, built an open world economy, promoted human rights and decolonization, and supported the transformation of Europe into a democratic, cooperative community of states, such that war between them has become unthinkable.//
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单项选择题 A1/A2型题

改善超声波指向性的方法除外（）

A.近场的长度

B.近场的扩散角

C.超声频率

D.增加探头直径

E.远场的范围
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