The first conclusive proof of Mendeleev's periodic theory came  in 1879, when Lars Nilson discovered this element, whose properties  matched a hypothetical element which Mendeleev had named "eka-  Boron.
The first conclusive proof of Mendeleev's periodic theory came  in 1879, when Lars Nilson discovered this element, whose properties  matched a hypothetical element which Mendeleev had named "eka-  Boron." A soft silvery metal, it has few industrial uses, on  account of its scarcity and high reactivity. FTP, name this  element lying between Calcium and Titanium on the periodic table,  which is named for Nilson's native region.
The first conclusive proof of Mendeleev's periodic theory came  in 1879, when Lars Nilson discovered this element, whose properties  matched a hypothetical element which Mendeleev had named "eka-  Boron.
{Scandium}