TED演讲:摩尔有多大(1)

 　　OK, today we're going to talk about the mole¹. 今天我们来谈一下摩尔。

　　Now, I know what you're thinking: "I know what a mole is, 我知道你现在在想：“我知道摩尔是什么，

　　it's a small furry² creature that digs holes in the ground and destroys gardens." 它是毛茸茸的小生物，挖洞和破坏花园。”

　　And some of you might be thinking that it's a growth on your aunt's face with hairs sticking out of it. 有些人也许会认为它是阿姨脸上带有几根细毛的痣。

　　Well, in this case, a mole is a concept that we use in chemistry to count molecules³, atoms, just about anything extremely small. 但今天所讲的摩尔，是化学中的一个概念，用来计算分子、或是任何极小物质的数量。

　　Have you ever wondered how many atoms there are in the universe? Or in your body? Or even in a grain of sand? 你曾经想过这个宇宙，或是你的身体、或是一粒沙子里到底有多少原子吗？

　　Scientists have wanted to answer that question, but how do you count something as small as an atom? 科学家想解决这个问题，但是你要如何计算小到像原子一样的东西？

　　Well, in 1811, someone had an idea that if you had equal volumes of gases, 在1811年，有个人突发奇想，认为如果气体体积相同，

　　at the same temperature and pressure, they would contain an equal number of particles. 在同等温度及压力下，它们应该会有相同的分子数量。

　　His name was Lorenzo Romano Amedeo Carlo Avogadro. 这个人的名字是阿莫迪欧阿伏加德罗。

　　I wonder how long it took him to sign autographs. 我很好奇他签个名要花多长时间。

　　Unfortunately for Avogadro, most scientists didn't accept the idea of the atom, 不幸的是，大部分科学家不接受这个想法，

　　and there was no way to prove he was right. 而他也没有方法可以证明他是对的。

　　There was no clear difference between atoms and molecules. 原子和分子之间并没有明显的差异。

　　Most scientists looked at Avogadro's work as purely⁴ hypothetical, and didn't give it much thought. 大多数科学家认为阿伏加德罗的理论纯粹是个假说，并没有特别去思考这件事。

　　But it turned out he was right! By late 1860, Avogadro was proven correct,  但事实证明他是对的！1860年底，阿伏加德罗的想法被证明是对的，

　　and his work helped lay the foundation for the atomic theory. Unfortunately, Avogadro died in 1856. 而且他的努力奠定了原子理论的基石。不幸的是，阿伏加德罗死于1856年。

　　Now the thing is that the amount of particles in even small samples is tremendous.  现在的问题是，即使是小东西，它上面的分子总数也是非常巨大的。

　　For example, if you have a balloon of any gas at zero degrees Celcius, 比如，假使你有一个装有任何气体的汽球，

　　and at a pressure of one atmosphere, then you have precisely⁵ six hundred and two sextillion gas particles. 在零摄氏度和一大气压的条件下，那你会有602乘10的21次方个气体分子。

　　That is, you have six with 23 zeros after it particles of gas in the container. 就是6后面带有23个0，这么多个分子在里面。

　　Or in scientific notation⁶, 6.02 times10 to the 23rd particles. 或用科学记号表示为6.02×10的23次方个分子。

　　This example is a little misleading, because gases take up a lot of space due to the high kinetic⁷ energy of the gas particles,  这个例子有点儿误导人，因为高动能的气体分子会占用较大的空间，

　　and it leaves you thinking atoms are bigger than they really are. 这让你感觉原子比原来的大。

　　Instead, think of water molecules. 相对地，我们看一下水分子。

　　If you pour 18.01grams of water into a glass, which is 18.01 milliliters,  如果你倒18.01克的水到杯子里，就是18.01毫升，

　　which is like three and a half teaspoons⁸ of water, you'll have 602 sextillion molecules of water. 大约是三个半茶匙的水，你就有602乘以10的21次方个水分子。

　　Since Lorenzo Romano, uh, never mind, Avogadro was the first one to come up with this idea, 自从洛伦佐·罗马诺...嗯，算了。阿伏加德罗是第一位提出这个想法的人，

　　scientists named the number 6.02 times 10 to the 23rd after him. 科学家用他的名字来命名6.02乘以10的23次方这个数字。

　　It is simply known as Avogadros's number. 这就是熟知的阿伏加德罗常数。

1 mole   

n.胎块；痣；克分子

参考例句：

• She had a tiny mole on her cheek.她的面颊上有一颗小黑痣。
• The young girl felt very self- conscious about the large mole on her chin.那位年轻姑娘对自己下巴上的一颗大痣感到很不自在。

2 furry   

adj.毛皮的；似毛皮的；毛皮制的

参考例句：

• This furry material will make a warm coat for the winter.这件毛皮料在冬天会是一件保暖的大衣。
• Mugsy is a big furry brown dog,who wiggles when she is happy.马格斯是一只棕色大长毛狗，当她高兴得时候她会摇尾巴。

3 molecules   

分子( molecule的名词复数 )

参考例句：

• The structure of molecules can be seen under an electron microscope. 分子的结构可在电子显微镜下观察到。
• Inside the reactor the large molecules are cracked into smaller molecules. 在反应堆里，大分子裂变为小分子。

4 purely   

adv.纯粹地，完全地

参考例句：

• I helped him purely and simply out of friendship.我帮他纯粹是出于友情。
• This disproves the theory that children are purely imitative.这证明认为儿童只会单纯地模仿的理论是站不住脚的。

5 precisely   

adv.恰好，正好，精确地，细致地

参考例句：

• It's precisely that sort of slick sales-talk that I mistrust.我不相信的正是那种油腔滑调的推销宣传。
• The man adjusted very precisely.那个人调得很准。

6 notation   

n.记号法，表示法，注释；[计算机]记法

参考例句：

• Music has a special system of notation.音乐有一套特殊的标记法。
• We shall find it convenient to adopt the following notation.采用下面的记号是方便的。

7 kinetic   

adj.运动的；动力学的

参考例句：

• There exist many sources of energy both potential and kinetic.存在着许多势能和动能的能源。
• The kinetic theory of gases is the best known example.气体动力学理论就是最有名的例子。

8 teaspoons   

n.茶匙( teaspoon的名词复数 )；一茶匙的量

参考例句：

• Add two teaspoons of salt. 加两小匙盐。
• Add 3 heaped teaspoons of sugar. 加满满的三匙糖。 来自《简明英汉词典》