题干

观察下列模型并结合有关信息,判断有关说法不正确的是(   ) 
 
B12结构单元
SF6分子
S8分子
HCN
结构模型示意图




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A:单质B12属原子晶体,结构单元中含有30个B-B键,含20个正三角形

B:SF6是由极性键构成的非极性分子

C:固态硫S8属于原子晶体

D:HCN的结构式为H-C≡N

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答案(点此获取答案解析)

C

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 When I was a junior high school student in 1980, God gave me a gift, it was happiness.

 One weekend, I went to visit my grandparents in the countryside. On my way home a car ran over me and cut off my  1  because of its high speed.

 Several days later when I woke up at the hospital, I realized I had to spend the rest of my life ­ 2  arms. How sad I felt at that time! Even I was full of fears. 3  slowly I knew I had to face the fact and got over it. I couldn't get my arms back even though I 4every day.

 However, it's easier  5  than done. It took me nearly half a year to get out of the sadness 6 . I got so much from my past story. From then on, I could treat my life with a  7 mind. But in our daily life, I often see my classmates  8  about little things: They get a bad grade on a test; their bus comes9; they don’t have a mobile phone but 10  have, and so on. But I only  11  life. I was lucky to realize from an accident : It is a waste of our life to focus on what you have 12 . We should always think of what we have. So why are so many people unhappy? Someone may say, “My whole life would improve 13  I have a new car.” But when you get the car and what 14  ? For a whole week you are walking on air. Then you go right back to being unhappy.

 Happiness depends on what we have! It’s in our heart. It’s a state of mind, even though you own the whole world, you may still feel15 .Happiness comes from mastering the art of appreciating(感激) and taking pleasure in what you really have.