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问题 填空题

用化学方程式表示下列原理：

（1）古代冶铜法（曾青得铁化为铜）：Fe+CuSO4______

（2）医药上用氢氧化铝治疗胃酸过多症：Al（OH）3+HCl______．

答案

（1））“曾青得铁则化为铜”，其中的“曾青”就是指硫酸铜；意思是说：硫酸铜溶液遇到金属铁时，铁与硫酸铜发生置换反应能生成金属铜，故该反应生成了铜和硫酸亚铁，该反应的化学方程式为：Fe+CuSO4═CuSO4+Fe；

（2）胃液中含有盐酸，胃酸过多会引起胃部不适，可用氢氧化铝来中和过多的盐酸，化学方程式为：3HCl+Al（OH）3═3H2O+AlCl3．

故答案为：（1）Fe+CuSO4═CuSO4+Fe；

（2）Al（OH）3+3HCl═3H2O+AlCl3．

选择题

对于放热反应H2 + Cl2  2HCl，下列说法正确的是

A．该反应涉及到了离子键和共价键的断裂与形成

B．反应物所具有的总能量高于产物所具有的总能量

C．断开1 mol H—H键和1 mol Cl—Cl键，所吸收的总能量，小于形成1 mol H—Cl键，所放出的能量

D．该反应中，化学能只转变为热能
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完形填空
完形填空（共20小题，每小题1分，满分20分）
阅读下面短文，从短文后各题所给的四个选项（A、B、C和D）中，选出可以填入空白处的最佳选项。
Our three-year-old daughter Becky wanted a dog. But we were too busy to buy one. One day, Becky ran in, shouting, “Mom! Come to see my dog!” Her face was red with   1 .
I followed her to the bush and found a   2 ! He was hurt. Seeing me, he stood up   3 ! I could see his teeth! God! My mouth felt dry. “Don’t be afraid. That’s Mom. She  4 you, too.” Becky said. Then he became friendly. It was  5 !
I   6  to find my husband and told him about the wolf. We should have  7  the wolf, but Becky loved him. Besides, he was gentle(温柔的) to Becky. So we called the vet finally.
Becky named the wolf (狼) Ralph ,  8  she carried food to him every day. Later, Ralph got well. They played together in the daytime. At night, Ralph would return to the mountains. Sometimes he   9  but came back several days later.
On Becky’s first day of school, we could see Ralph’s   10 . After the school bus left, Ralph lay by the side of the road and   11  . When Becky returned, he got happy again. This   12  throughout Becky’s school years.
Twelve   13  passed.
One day we heard that a she-wolf was killed. The other wolf was hurt and ran away. We were   14  about Ralph. That night, Ralph returned with a wound (伤). Fifteen-year-old Becky held his head and   15  him. We hope he could come through. However, he   16 .
Becky cried. I noticed something strange in the bush — two little yellow eyes! Ralph’s  17 ! Before he died, Ralph   18  his child to us! He knew he would be  19  here, as he had been. Ralph, Ralph. I was   20 .
“Don’t be afraid, little ... Ralphie. That’s Mom. She loves you, too.”
小题1:
A．encouragementB．entertainmentC．agreementD．excitement
小题2:
A．dogB．foxC．wolf D．tiger
小题3:
A．lovelyB．finallyC．suddenlyD．patiently
小题4:
A．hurtsB．lovesC．killsD．hates
小题5:
A．wonderfulB．unhappyC．unbelievableD．normal
小题6:
A．preparedB．rushed C．pretendedD．wanted
小题7:
A．lovedB．foundC．damagedD．killed
小题8:
A．andB．butC．soD．or
小题9:
A．disappearedB．turnedC．passedD．came
小题10:
A．sadnessB．dreamC．understandingD．anger
小题11:
A．sleptB．leftC．sangD．waited
小题12:
A．stoppedB．joinedC．livedD．continued
小题13:
A．daysB．weeksC．monthsD．years
小题14:
A．surprisedB．puzzledC．worriedD．careful
小题15:
A．comfortedB．beatC．washedD．amused
小题16:
A．succeededB．diedC．criedD．woke
小题17:
A．motherB．fatherC．wifeD．child
小题18:
A．postedB．broughtC．soldD．threw
小题19:
A．safeB．happyC．warmD．friendly
小题20:
A．confusedB．disappointedC．moved D．frightened
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