万物简史(MP3+中英字幕) 第150期:基本物质(18)
日期:2016-09-26 15:45

(单词翻译:单击)

Mendeleyev used a slightly different approach, placing his elements into groups of seven, but employed fundamentally the same principle. Suddenly the idea seemed brilliant and wondrously perceptive. Because the properties repeated themselves periodically, the invention became known as the periodic table.
门捷列夫采用了一种稍稍不同的方法,把每七个元素分成一组,但使用了完全相同的前提。突然之间,这方法似乎很出色,视角很清晰。由于那些特点周期性地重复出现,所以这项发明就被叫做"周期表"。
记元素周期表的困扰

Mendeleyev was said to have been inspired by the card game known as solitaire in North America and patience elsewhere, wherein cards are arranged by suit horizontally and by number vertically. Using a broadly similarconcept, he arranged the elements in horizontal rows called periods and vertical columns called groups. Thisinstantly showed one set of relationships when read up and down and another when read from side to side. Specifically, the vertical columns put together chemicals that have similar properties. Thus copper sits on topof silver and silver sits on top of gold because of their chemical affinities as metals, while helium, neon,and argon are in a column made up of gases. (The actual, formal determinant in the ordering is something called their electron valences, for which you will have to enroll in night classes if you wish an understanding.) The horizontal rows, meanwhile, arrange the chemicals in ascending order by the number of protons in their nuclei—what is known as their atomic number.
据说,门捷列夫是从北美洲的单人牌戏获得了灵感,从别处获得了耐心。在那种牌戏里,纸牌按花色排成横列,按点数排成纵行。他利用一种十分相似的概念,把横列叫做周期,纵行叫做族。上下看,马上可以看出一组关系;左右看,看出另一组关系。具体来说,纵列把性质类似的元素放在一起。因此,铜的位置在银的上面,银的位置在金的上面,因为它们都具有金属的化学亲和性;而氦、氖和氩处于同一纵行,因为它们都是气体。(决定排列顺序的,实际上是它们的电子价。若要搞懂电子价,你非得去报名上夜校。)与此同时,元素按照它们核里的质子数--叫做原子序数--从少到多地排成横列。

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