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问题 填空题

现有mg某气体，它由双原子分子构成，它的摩尔质量为Mg·mol-1。若阿伏加德罗常数用NA表示，则：（1）该气体的物质的量为________mol。

（2）该气体所含原子总数为_______ 个。

（3）该气体在标准状况下的体积为____________L。

（4）该气体在标准状况下的密度为____g/L。

答案

（1）m/M

（2）2mNA/M

（3）22.4m/M

（4）M /22. 4

单项选择题

Many students have hobbies, such as reading, painting, growing vegetables in their gardens, and looking after animals. Some hobbies are relaxing and (16) are creative. Hobbies can develop your interests and help you learn new skills.
David Smith is a student, and his hobby is writing. (17) the sumer of 2000, he spent four weeks on a summer camp. As well as the usual activities, such as sailing, climbing and mountain biking, there was a writing workshop with a professional (18) "She asked us to imagine that we were in a story. Then we wrote about our (19) at the camp. "
In senior high school David wrote a story about teenage life, and it (20) as a book in 2003. Many teenagers love his book, and as a result, David has become a (21) young writer.
David has been very lucky (22) his hobby has brought him enjoyment and success, but he is (23) interested in many other things. "I like playing volleyball, too" says David. "I spend some of my free time playing volleyball for my school team. (24) I’ll write more books in the future, but I’m not sure. "
It’s sometimes difficult (25) that we shouldn’t spend all our time on our favourite hobby. There are many other interesting things to do in life, and we should try to do something new or different.

Ⅱ. 完形填空/Cloze

A．or

B．but

C．because

D．though
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单项选择题

天气预报属计算机应用领域中的（）。

A.过程控制

B.辅助教学

C.远程教育

D.科学计算
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