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Dobereiner proposes the law of Triads
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62 elements have been discovered
By 1860, 62 elements have been discovered. Scientists start to discuss diffrent ways of arranging them. -
John Newlands comes up with the Law of Octives
John Newlands tried arranging the elements in order of similar properties. He noticed that every elements properties would corrospond with the elements 8 places away from it. -
Dmitri Mendeleev finds a way of ordering all the known elements
He organised the elements according to atomic mass in accending order, with the similar elements grouped vertically -
Lord Raleigh discoveres Argon
He eported it waa gas at roomtemprture and was very unreactive. It didn't ft ito any groupin the periodic table -
William Ramsy propses that Argon isput in a new group with Helium
He called his group group 0. He also accurately predicted the properties and existance of Neon. -
Henry Moseley changes how the perodic table is ordered
He orders it according to length or wavelngth, not atomic mass. This clears up alot of irreguaritys within the table