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问题 选择题

有人用铜、锌合金制成假金元宝，某同学用三种简便的化学实验揭穿了它，该同学一定不会用到的试剂是（  ）

A．盐酸

B．稀硫酸

C．AgNO3 溶液

D．NaCl溶液

答案

答案：D

A、合金中的锌能与盐酸反应生成氢气，表面冒气泡，故A正确；

B、合金中的锌能与硫酸反应生成氢气，表面冒气泡，，故B正确；

C、合金中的铜和锌能与硝酸银反应生成银，表面有银白色金属析出，故C正确；

D、铜和锌都不与氯化钠反应，无法证明，故D错误．

故选D．

问答题

I know a valley in North Wales, between the mountains and the sea. It is a beautiful valley, snug, comfortable, sheltered by the mountains from all the bitter blasts. But it is very enervating, and I remember how the boys were in the habit of climbing the hill above the village to have a glimpse of the great mountains in the distance, and to be stimulated and freshened by the breezes which came from the hilltops, and by the great spectacle of their grandeur. We have been living in a sheltered valley for generations. We have been too comfortable and too indulgent—many, perhaps, too selfish—and the stern hand of fate has scourged us to an elevation where we can see the great everlasting things that matter for a nation—the great peaks we had forgotten, of Honour, Duty, Patriotism, and, clad in glittering white, the great pinnacle of sacrifice pointing like a rugged finger to Heaven. We shall descend into the valleys again; but as long as the men and women of this generation last, they will carry in their hearts the image of those great mountain peaks.
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填空题

饭店员工职业培训的形式有：（）培训、（）培训和（）培训。
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