题干

A.活性炭B.二氧化碳C.干冰D.二氧化硫E.氮气F.一氧化碳,选择正确答案的化学式填空:

①形成酸雨的主要物质是____

②可用于人工降雨和舞台制造“云雾”效果的物质是____

③具有吸附性,净水器中常使用的物质是____

④香烟燃烧产生的能与血液中血红蛋白结合的有毒气体是____

⑤能使澄清石灰水变浑浊的是____

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答案(点此获取答案解析)

SO2,CO2,C,CO,CO2

同类题3

阅读下面短文,掌握其大意,然后从各小题所给的四个选项中选出最佳选项。

    One thorn(刺) of experience is worth many times of warning.

    Ralph Wick was seven years old. In most things he was a fine boy, but he would cry from time to time. When he could not have what he wanted, he would 1for it. If he was told that it would hurt him, and he could not 2 it, he would also cry.

    One day, he went with his mother into the 3. The sun shone. The grass was cut. The flowers were starting to come out.

    Ralph thought he was, for once, a good boy. A 4 was on his face. He wished to do as he was told. Ralph helped his mother with the farm work and he was very happy.

    “Now you must be tired and 5,” said his mother. “Have a good rest here and eat some cookies. I will get a beautiful red rose for you.” So his mother brought the red flower to him. When he saw his mother still had a white rose in her hand, Ralph 6 it.

    “No, my dear.” said his mother. “See how many thorns it has. You must not touch it, or you would be sure to hurt your 7.” When Ralph found that he could not have the white rose, he began to cry, and 8 took it away. But he was soon very sorry. The thorns hurt his hand. It was so 9 that he could not use it for some time.

    Ralph would never 10 this. From then on, when he wanted what he should not have, his mother would point to his hand which had been hurt before. He at last learned to do as he was told.