问题 填空题

现有下列物质:①铜    ②熔融氯化钠    ③氯化氢    ④CO2⑤NaHSO4 固体   ⑥氨水

按物质的分类方法填写表格的空白处:(填编号)

分类标准能导电的物质电解质非电解质
属于该类的物质

答案

①铜虽能导电,但它是单质,它既不是电解质也不是非电解质;

②熔融氯化钠中有自由移动的钠离子和氯离子,能导电,氯化钠是化合物,是电解质;

③氯化氢,是纯净物,只存在氯化氢分子,不能导电,氯化氢水溶液能导电,是由于电离出自由移动的氢离子和氯离子,氯化氢是化合物,属于电解质; 

④CO2,是化合物,二氧化碳分子不导电,二氧化碳溶于水,能电离出自由移动的氢离子和碳酸根离子,能导电,但这些离子是碳酸电离,不是它自身电离,故二氧化碳是非电解质;

⑤NaHSO4 固体,没有自由移动的离子,不导电,但在水溶液中或在熔融状态下,有自由移动的离子,能导电,硫酸氢钠是化合物,所以硫酸氢钠为电解质;

⑥氨水,是氨气的水溶液,NH3H2O⇌NH4++OH-,有自由移动的铵根离子和氢氧根离子,能导电,氨水是溶液,所以既不是电解质,也不是非电解质;

故答案为:①②⑥;②③⑤;④.

阅读理解

阅读理解。

     Americans love sports-they love to play them, to watch them on televisions, and to talk about them. But this hobby sometimes has serious results-at least to the players. For example, when people play tennis, sometimes they hurt their elbow and in this way they develop "tennis elbow". Also it is easy to hurt knees in

a football game. These injuries happen while the player is having fun, but they still hurt. A few months ago, Kathleen

     Simmons, who loves playing volleyball, hurt her knee in a volleyball game. Her doctor told her that she needed a very difficult operation (手术) or she might not be able to play again,

     She felt very sad and didn't know what to do. Then Simmons learned about "video operation". With the help of this new science in medicine, doctors can now repair many injuries and get people back on the playing field and back to their jobs much faster. Simmons found a hospital that was using this new science and went to see the doctors there. The doctors told her the operation could help. For this operation, her doctor didn't have to open her knee. Instead he put a very small camera lens (镜头) inside her knee. The lens sent back pictures, which appeared on a television screen. As he worked, he could see the inside of her knee

on the TV. With the help of the large pictures on the screen, the doctor knew exactly what to do when he was making the repairs.

     Simmons started walking five days after her operation. " My knee hurt a lot the first few days," she

said.  "But I felt better very quickly. " Now, six months after her operation,

     Simmons can do everything she did before her injury. "It feels like a new knee," she said.  "I can even

play volleyball again. "

根据短文内容,回答下列问题 。

1. Do Americans love sports?

    ___________________________________________

2. What sport is Simmons interested in?

    ___________________________________________

3. What did the doctor put inside Simmons' knee?

    ___________________________________________

4. What problem may people have when they play sports?

    ___________________________________________

5. What's the advantage of the new science?

    ___________________________________________

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