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Metals, Non-metasl and "earths"
Antoine-Laurent de Lavoisier seperated all the elements into these 3 categories. -
All 36 known elements given their own chemical symbol and ordered by mass.
John Dalton -
Now 55 elements in total
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Johann Dobereiner Catergorized them into "triads"
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All 60 known elements catergorized in order of mass
This formed 7 columns. -
Dmitri Mendeleev constructed a table of rows and columns
He placed each element in it's own boc. horizontally according to atomic mass and vertically according to their properties. Thi left gaps in his table for elements that e theorised to not ave been discovered yet. -
Gallium discovered
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Scandium discovered
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Germanium
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technitium dicovered
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My friend and i creating this timeline for SCIENCE!!