In 1817, Johann Wolfgang Dobereiner thought that he had made a great
observation about elements.
He thought that there was a relationship between the atomic weights
of elements and their properties.
His theory was that, in groups of three (triads), the middle element had
the mean atomic mass of the two elements to either side of it.
This works with many elements, like Lithium, Sodium and Potassium.
(Li + K) / 2 = Na (7 + 39) / 2 = 23 (jan 1, 1817 – 23h 59min, dec 31, 1817 y)
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Key Scientists in the construction of the periodic timetable
Chemistry homework for the 30/11/18 detailing the title
Date:
