The Early Periodic Table
The early classification of Antoine Lavoisier in 1789
The understanding of the periodic table was very basic. Unfortunately, lots of his periodic table was full of compounds that he didn’t understand at the time. This periodic table classified all of the elements into four ‘elemental’ groups. Acid-making elements, Gas-like elements, Metallic elements and earthy elements.
The works of Johann Dobereiner from 1828 -1829
Döbereiner was amongst the first scientists to recognise the 'group' idea of chemically very similar elements. Three groups he 'recognised' were (i) Group 1 Alkali Metals, (ii) Group 2 Alkaline Earth Metals, (iii) Group 7 Halogens.