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Periodic Table Turns 150 Years Old
The Economist tells the story of how French chemist Antoine-Laurent de Lavoisier came to publish the first putatively comprehensive list of chemical elements -- substances incapable of being broken down by chemical reactions into other substances -- known today as the periodic table. It was Lavoisier and his wife Marie-Anne who pioneered the technique of measuring quantitatively what went into and came out of a chemical reaction, as a way of getting to the heart of what such a reaction really is. "Where the story of the periodic table of the elements really starts is debatable," reports The Economist, "but Lavoisier's laboratory is as good a place as any to begin..." Here's an excerpt from the report: Lavoisier's list of elements, published in 1789, five years before his execution, had 33 entries. Of those, 23 -- a fifth of the total now recognized -- have stood the test of time. Some, like gold, iron and sulphur, had been known since ancient days. Others, like manganese, molybdenum and tungsten, were recent discoveries. What the list did not have was a structure. It was, avant la lettre, a stamp collection. But the album was missing.
Creating that album, filling it and understanding why it is the way it is took a century and a half. It is now, though, a familiar feature of every high-school science laboratory. Its rows and columns of rectangles, each containing a one- or two-letter abbreviation of the name of an element, together with its sequential atomic number, represent an order and underlying structure to the universe that would have astonished Lavoisier. It is little exaggeration to say that almost everything in modern science is connected, usually at only one or two removes, to the periodic table. |
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Jennifer Garner |
It's about getting the kids up and fed, getting one to school, getting the other down for a nap, going to the grocery store, picking one up from school, getting the other one down for another nap, cooking dinner... I live my life at these two extremes. I'm either a full-time stay-at-home mom or a full-time actress. |
Craig Ferguson |
I came to America, and I made good. It's an old story, but it hasn't been told in a long time. Usually, it's, 'I'm an immigrant, I came here and got persecuted.' My story is I came here, I worked hard, and it worked out all right. So it's still available. |