问题
实验题
若已知一滴油的体积为V，它在液面上展开的单分子油膜面积为S，油的摩尔质量为M，密度为ρ，则阿伏加德罗常数可表示为____________.
答案
由油膜法测分子直径原理知：分子直径d=
，所以单个分子体积V0=
π（
）3=
，所以单个分子的质量m=ρV0=
又因为油的摩尔质量为M，所以阿伏加德罗常数NA=
=.
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若已知一滴油的体积为V，它在液面上展开的单分子油膜面积为S，油的摩尔质量为M，密度为ρ，则阿伏加德罗常数可表示为____________.
由油膜法测分子直径原理知：分子直径d=，所以单个分子体积V0=π（）3=，所以单个分子的质量m=ρV0=
又因为油的摩尔质量为M，所以阿伏加德罗常数NA==.
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| Most people believe they don’t have much imagination. They are 1 . Everyone has imagination, but most of us, once we become adults, forget how to 2 it. Creativity isn’t always 3 with great works of art or ideas. People at work and in their free time 4 think of creative ways to solve problems. Maybe you have a goal to achieve, a tricky question to answer or you just want to expand your mind! Here are three techniques to help you. Making connections. This technique involves taking 5 ideas and trying to find links between them. First, think about the problem you have to solve or the job you need to do. Then find an image, word, idea or object, for example, a candle. Write down all the ideas/words 6 with candles: light, fire, matches, wax, night, silence, etc. Think of as many as you can. The next stage is to relate the 7 to the job you have to do. So imagine you want to buy a friend an original 8 ; you could buy him tickets to match or take him out for the night. NO limits! Imagine that normal limitations don’t 9 . You have as much time /space / money, etc. as you want. Think about your goal and the new 10 . If your goal is to learn to ski, 11 , you can now practise skiing every day of your life (because you have the time and the money). Now 12 this to reality. Maybe you can practise skiing every day in December, or every Monday in January. Be someone else! Look at the situation from a 13 point of view. Good businessmen use this technique in trade, and so do writers. Fiction writers often imagine they are the 14 in their books. They ask questions: What does this character want? Why can’t she get it? What changes must she make to get what she wants? If your goal involves other people, put yourself in their 15 . The best fishermen think like fish! | ||||
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