17 agos 1821 anni - Discovered how the relative atomic mass of the middle element in a group of three is almost halfway between the lightest and heaviest ones in the group. He called this pattern “triad”. He organized many of the elements that (at the time) were discovered that way. The difference of relative atomic mass between three elements.
Aggiunto al nastro di tempo:
Data:
17 agos 1821 anni
Adesso
~ 204 years ago