万物简史 第135期:基本物质(7)
And his fancy equipment did in fact come in very handy. For years, he and Madame Lavoisier occupied themselves with extremely exacting studies requiring the finest measurements. They determined, for instance, that a rusting object doesn't lose weight
万物简史 第136期:基本物质(8)
In 1793, the Reign of Terror, already intense, ratcheted up to a higher gear. In October Marie Antoinette was sent to the guillotine. The following month, as Lavoisier and his wife were making tardy plans to slip away to Scotland, Lavoisier was arres
万物简史 第137期:基本物质(9)
In the early 1800s there arose in England a fashion for inhaling nitrous oxide, or laughing gas, after it was discovered that its use was attended by a highly pleasurable thrilling. For the next half century it would be the drug of choice for young p
万物简史 第138期:基本物质(10)
Things might have been worse had it not been for a splendidly improbable character named Count von Rumford, who, despite the grandeur of his title, began life in Woburn, Massachusetts, in 1753 as plain Benjamin Thompson.Thompson was dashing and ambit
万物简史 第139期:基本物质(11)
In between these undertakings, he somehow found time to conduct a good deal of solid science. He became the worlds foremost authority on thermodynamics and the first to elucidate the principles of the convection offluids and the circulation of ocean
万物简史 第140期:基本物质(12)
Soon after taking up his position, Davy began to bang out new elements one after anotherpotassium, sodium,magnesium, calcium, strontium, and aluminum or aluminium, depending on which branch of English you favor. 上任不久,戴维开始宣布发现一
万物简史 第141期:基本物质(13)
Fortunately more sober types were at work elsewhere. In 1808, a dour Quaker named John Dalton became the first person to intimate the nature of an atom (progress that will be discussed more completely a little further on), and in 1811 an Italian with
万物简史 第142期:基本物质(14)
No one knew about his principle, because Avogadro himself was a retiring fellow, he worked alone, corresponded very little with fellow scientists, published few papers, and attended no meetings but also it was because there were no meetings to attend
万物简史 第143期:基本物质(15)
Because chemists for so long worked in isolation, conventions were slow to emerge. Until well into the second half of the century, the formula H2O2 might mean water to one chemist but hydrogen peroxide to another. C2H4 could signify ethylene or marsh
万物简史 第144期:基本物质(16)
Despite the occasional tidyings-up, chemistry by the second half of the nineteenth century was in something of a mess, which is why everybody was so pleased by the rise to prominence in 1869 of an odd and crazed-looking professor at the University of
万物简史 第145期:基本物质(17)
Mendeleyev dutifully completed his studies and eventually landed a position at the local university. There he was a competent but not terribly outstanding chemist, known more for his wild hair and beard, which he had trimmed just once a year, than fo
万物简史 第146期:基本物质(18)
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 periodic
万物简史 第147期:基本物质(19)
The structure of atoms and the significance of protons will come in a following chapter, so for the moment all that is necessary is to appreciate the organizing principle: hydrogen has just one proton, and so it has an atomic number of one and comes
万物简史 第148期:基本物质(20)
For most of us, the periodic table is a thing of beauty in the abstract, but for chemists it established an immediate orderliness and clarity that can hardly be overstated. Without a doubt, the Periodic Table of the Chemical Elements is the most eleg
万物简史 第149期:基本物质(21)
The nineteenth century held one last great surprise for chemists. It began in 1896 when Henri Becquerel in Paris carelessly left a packet of uranium salts on a wrapped photographic plate in a drawer. When he took theplate out some time later, he was