To explain aether, this scientist predicted the existence of two elements lighter than hydrogen, one
To explain aether, this scientist predicted the existence of two elements lighter than hydrogen, one of which he named coronium. This man also described and predicted the properties of "ekaaluminum" and "ekaboron", (*) elements known today as gallium and scandium. This man's most famous discovery was described in his book, Principles of Chemistry, and attempted to classify the elements by their chemical properties. For ten points, name this Russian chemist credited with creating the first Periodic Table.
To explain aether, this scientist predicted the existence of two elements lighter than hydrogen, one of which he named coronium.
Dmitri Ivanovich {Mendeleev}