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劍9閱讀真題原文1williamhenryperkin-wenkub

2023-04-11 01:28:41 本頁面
 

【正文】 to attend the Royal College of Chemistry, which he succeeded in entering in 1853, at the age of 15.At the time of Perkin’s enrolment, the Royal College of Chemistry was headed by the noted German chemist August Wilhelm Hofmann. Perkin’s scientific gifts soon caught Hofmann’s attention and, within two years, he became Hofmann’s youngest assistant. Not long after that, Perkin made the scientific breakthrough that would bring him both fame and fortune.At the time, quinine was the only viable medical treatment for malaria. The drug is derived from the bark of the cinchona tree, native to South America, and by 1856 demand for the drug was surpassing the available supply. Thus, when Hofmann made some passing ments about the desirability of a synthetic substitute for quinine, it was unsurprising that his star pupil was moved to take up the challenge.During his vacation in 1856, Perkin spent his time in the laboratory on the top floor of his family’s house. He was attempting to manufacture quinine from aniline, an inexpensive and readily available coal tar waste product. Despite his best efforts, however, he did not end up with quinine. Instead, he produced a mysterious dark sludge. Luckily, Perkin’s scientific training and nature prompted him to investigate the substance further. Incorporating potassium dichromate and alcohol into the aniline at various stages of the experimental process, he finally produced a deep purple solution. And, providing the truth of the famous scientist Louis Pasteur’s words ‘chance favours only the prepared mind’, Perkin saw the potential of his unexpected find.Historically, textile dyes were made from such natural sources as plants and animal e
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