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...added his ideas to the theory of matter, the Greeks and people of the eras after that only knew that elements and atoms existed, not what they made up, were made out of or did.
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All dates have been written as January 1st, due to the fact that no specific day is known for each event. Some discoveries took a year or more to develop.
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...the first person to compile a list of elements. He knew of 33 elements, and was able to distinguish between metals and non-metals. A chemist, John Dalton, then decided that the mass of elements were what determined the properties.
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...a table of atomic weights for the elements known in the 1800s. He also introduced to the idea of using letters to represent the elements, rather than Greek symbols which had been previously used.
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...the atomic weights of the known elements, and decided that they should be arranged in order of weight, starting with hydrogen.
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...was three dimensional! A geologist, Alexandre-Émile Béguyer de Chancourtois, created the first accurate periodic table, which he called the 'vis Tellurique' - It was shaped like a cylinder.
de Chancourtois came to the conclusion of using that shape due to his work with globes. -
...the first flat periodic table. He also predicted that of the thirty or forty elements he listed in his table, there would be a lot more. This idea was dismissed until the discovery of gallium and germanium in 1875 and 1886.
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...created a periodic table that included 56 elements. Both Meyer and Mendeleev are known for creating tables that have influenced the periodic table we use today.
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...helium, neon, krypton and xenon. He also worked with argon. His discoveries and experimentation led to whole new group being added to the periodic table.
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...attempted to revive the de Chancourtois three dimensional periodic table by developing the cylinder into a spiral or ribbon. Others tried to redesign the periodic table so that it was a simple rectangule.
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...the periodic table by nuclear charge, as opposed to atomic weight. He decided this after measuring the X-ray wavelengths of elements.
Mosely also showed that there were gaps in the periodic table. These gaps are now known as technetium and promethium. -
...the table. This was known as the "Periodic Chart of the Atoms"
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...rearranged the periodic table so that the 'created' elements, the Transactinides, would fit in.
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......that the 'Alexander Arrangement' of the periodic table is the most correct, but for educational purposes, the two dimensional periodic table (that we use nowadays) is favoured for it's simplicity.
