jan 1, 1902 - Changes to the periodic table P2
Description:
In 1902, Mendeleev wrote those elements should be put in a new group he said this idea was consistent with what Ramsay suggested to him and referred to Errera as to the first person to suggest the idea. Mendeleev himself added these elements to the table as group 0 in 1902, without disturbing the basic concept of the periodic tableAdded to timeline:
Date:
jan 1, 1902
Now
~ 123 years ago