题目

根据氨气还原氧化铜的反应，可设计测定铜元素相对原子质量么 (近似值)的实验。先称量反应物氧化铜的质量m(CuO)，反应完全后测定生成物水的质量m(H20)，由此计算。为此，提供的实验仪器及试剂如下(根据需要可重复选用，加入的NH4C1与Ca(OH)2的量足以产生使CuO完全还原的氨气)： 请回答下列问题：     (1)氨气还原炽热氧化铜的化学方程式为________________________________；     (2)从所提供的仪器及试剂中选择并组装本实验的一套合理、简单的装置，按气 阅读下列短文, 从所给的四个选项中, 选出最佳答案。 　　    　　Tony and Maria were twins (双胞胎). When they were seven, their parents gave them a parrot (鹦鹉) 1 . Its name was Chico and they kept it in a large cage in the living-room. Chico soon learned to say a few words. 　　    　　 When the children were at home, Chico's cage door was opened and the parrot 2 . Sometimes he landed on Maria's arm;sometimes he landed on Tony's shoulder. One day he 3 and very nearly fell into the　　 fire. 　　    　　 Tony put the parrot on his arm. He 4 the fire and said,　　 "Fire-bad!" Over and over again. Chico learned the words, and said　　 "Fire-bad!" if 5 carried him near the fire. 　　    　　 One very cold night, just before bed-time, Tony put lot of coal on the living-room fire, but he 6 the fire-guard (火炉栏) in front　　 of the fire. 　　    　　 Dad then 7 the light and the family went to bed. Soon everybody in the house was 8 .　　 Chico was first to 9 . He at once saw that a bit of burning coal 10 out of the fire onto the rug (炉边地毯). Smoke and flames (火焰) were rising from the rug. 　　    　　 "Fire-bad! Fire-bad!" screamed (尖叫) Chico, as he jumped about his cage. Dad was first to be waken (醒来). He ran downstairs. Then came Mum, Tony, and Maria. Mum and Dad filled pails (桶) of water and threw them on the burning rug. Tony put the fireguard in front of the fire. Maria spoke quietly to Chico 11 . In a few minutes, the fire was 12 . But if Chico had not cried out, the house 13 . 　　    　　 "Thank you, My dear friend—Chico. You're a hero." said Tony, 14 .　　 Then they went upstairs, 15 in his cage. 　　 1. A. for their youngest    B. to the birthday C. for their birthday　　   D. on their celebration [    ] 2. A. refused to fly into the blue sky   B. flew out of the cage C. still stayed in the cage　　　　　　  D. flow down to the ground [    ] 3. A. became tiring　　    B. got angry C. got ill　　　　　　　　 D. became tired [    ] 4. A. looked at    B. pointed out C. pointed to　　  D. looked for [    ] 5. A. anyone　　 B. someone C. everyone　　  D. on one [    ] 6. A. forgot putting    B. forgot to put C. forgot having put    D. forgot to have put [    ] 7. A. put on　　  B. put down C. put out　　    D. put away [    ] 8. A. almost dying    B. very asleep C. fast sleeping　　  D. fast asleep [    ] 9. A. sit up   B. stand up C. wake up　　 D. eat up [    ] 10.A. had fallen   B. fell C. had felt　　    D. had been fallen [    ] 11.A. to carry him back into the bag　　 B. to keep him calm C. to let him fly into the sky　　　　   D. to make him calmly [    ] 12.A. being put away    B. put out C. put down　　　　　　 D. putting out [    ] 13. A. might have been burned down    B. had burned down at once C. might have been burning down　　   D. might have burned bown [    ] 14. A. to speak to all of them  B. speaking to all of them C. to speak for them all　　    D. speaking for them all [    ] 15. A. to leave a happy Chico resting B. left a happy Chico to rest C. leaving a happy Chico resting 　　　　 D. having left a happy Chico to rest 　　　　 [    ]