Historical Development of the Atom

The notion of the atom all stared about 450 BC when a Greek scholar starting think when can something break on more, when are the pieces at their smallest, this mans name was Leucippus. Leucippus also had pupil who also thought the same way as Leucippus, his name was Democritus. They developed there ideas and when Democritus died his theory summed up briefly was that everything in the world was made of tiny pieced that could not be broken up any more. That how the word atom was derived from the Greek work "atomos" meaning "unbreakable". This was the start of the theory of atoms. The first time this theory was taught at a school was by Epicurus 306 BC which he established himself.

The theory laid dormant for about 2 millenniums this was basically because it was all but forgotten, this was because it had no evidence, and it was only logic. One of the first people to show some evidence was Robert Boyle, an English chemist. In 1662 he conducted 'Boyle's experiment and compressed air in a 'J' tube with mercury, this opened up a whole new window.

This lead to new and old thought about different types of atoms, elements. The Greeks thought simular to this but only divided it up into four groups. Their theory was close to Boyle's but Boyle had a more concise idea of these elements and by the end of the 1700's they had discovered about 30 elements.

In 1972 Frenchman Antoine Laurent Lavoisier discover the no mater what happens a substance always has the same weight. In the late 1700's another Frenchman, Proust, discovert that elements can be combined to make different compounds, and that certain proportions had to be used. This became know as "law of definite proportions".

A few years later an English chemist, John Dalton, a fan of Boyle worked on Proust's theory and came up with "the law of multiple proportions". Dalton soon came up with 'weight' theories of the atom a discovered that hydrogen was the lightest.

In 1813 Jons Jakob Berzelius created a system using the Latin words for the element to represent that element.

In 1860 the chemist of Europe had their first international Chemical Congress to discuss the matter. They theory that prevailed was Cannizzaro theory.

John Thomson was born in 1856, and is recognised as the British scientist who discovered and identified the electron.

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