Examples are: gallium, germanium, technetium etc.
I think to atomic weight and density.
Ga, Sc and Ge were important to Mendeleev because these three elements have the same physical and chemical properties.
Yes. Mendeleev did group elements in similar properties.
Mendeleev arranged the elements according to their atomic weight and valence.
DiscoVery of new elements
Dmitri Mendeleev developed the first periodic table of the elements.
Ga, Sc and Ge were important to Mendeleev because these three elements have the same physical and chemical properties.
Yes. Mendeleev did group elements in similar properties.
The most important principle was the listing in groups, after similar chemical or physical properties.
Gallium which had the properties that Mendeleev predicted
Mendeleev arranged the elements according to their atomic weight and valence.
Chemical elements arrangement was the object of study for Mendeleev.
Mendeleev was able to predict the properties of the elements that were not discovered at that time. He left gaps for these elements in his Periodic Table.
Mendeleev arranged the elements in the increasing order of their atomic masses and repeating properties.
Dmitri Ivanovich Mendeleev was a Russian chemist and inventor. He is credited as being the creator of the first version of the periodic table of elements. Using the table, he predicted the properties of elements yet to be discovered.
Independently by Dmitri Mendeleev and Lothar Meyer in 1869
The usefulness of Mendeleev's periodic table was confirmed by the discovery of elements with predicted properties.
Dmitri mendeleev arranged elements in order of increasing atomic masses. He considered chemical properties of the elements, their oxides and nitrides.