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Lecture on John Dalton. John Dalton (1776 – 1844) was an English chemist, meteorologist and physicist. Later, Thompson, Rutherford Bohr, Schrodinger and many others contributed to our present model of the atom.
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Lecture on John Dalton www.assignmentpoint.com
John Dalton (1776 – 1844) was an English chemist, meteorologist and physicist. Later, Thompson, Rutherford Bohr, Schrodinger and many others contributed to our present model of the atom. www.assignmentpoint.com
Chemist John Dalton was born September 6, 1766, in Eaglesfield, England. During his early career, he identified the hereditary nature of red-green color blindness. In 1803 he revealed the concept of Dalton’s Law of Partial Pressures. Also in the 1800s, he was the first scientist to explain the behavior of atoms in terms of the measurement of weight. Dalton died July 26, 1844 in Manchester, England. www.assignmentpoint.com
Matter, though divisible in an extreme degree, is nevertheless not infinitely divisible. That is, there must be some point beyond which we cannot go in the division of matter. ... I have chosen the word “atom” to signify these ultimate particles. John Dalton www.assignmentpoint.com
Dalton's Law Dalton's interest in atmospheric pressures eventually led him to a closer examination of gases. While studying the nature and chemical makeup of air in the early 1800s, Dalton learned that it was not a chemical solvent, as other scientists had believed. Instead it was a mechanical system composed of small individual particles that used pressure applied by each gas independently. www.assignmentpoint.com
While parts of Dalton’s atomic theory were correct, today’s model of the atom with electrons, protons and neutrons did not emerge until the middle of the 20th century. In the modern era, who revived and formalized the concept of atoms originally proposed in ancient Greece by Democritus? For 2000 years prior to this revival, the commonly accepted concept that matter is continuous has been attributed to Plato and Aristotle. www.assignmentpoint.com
Death and Legacy After suffering a second stroke, Dalton died quietly on the evening of July 26, 1844, at his home in Manchester, England. He was provided a civic funeral and granted full honors. A reported 40,000 people attended the procession, honoring his contributions to science, manufacturing and the nation's commerce. www.assignmentpoint.com