Because at that time there were no known elements to fill those gaps. The fact that they were filled indicated the power of his classification method. When a scientific theory predicts things clearly and these are later found, the theory becomes validated.
Dmitri Mendeleev first periodic table is called Mendeleev's periodic table. Elements are arranged according to atomic mass.
The first element of the Mendeleev's periodic table is hydrogen (H).
Hydrogen is the first chemical element in the Periodic Table of Mendeleev.
Publishing the first Periodic Table.
Dmitri Mendeleev is considered the father of the periodic table. He created the first widely accepted version of the periodic table in 1869, arranging elements based on their properties and atomic weights. Mendeleev's table laid the groundwork for the modern periodic table.
He made the first periodic table.
Because those elements were not known when he formulated his periodic table.
Because
The first periodic table was organized by Dmitri Mendeleev in 1869. Mendeleev arranged elements according to their atomic weight and properties, leaving gaps for unknown elements that were later discovered.
The first element in the periodic table of Mendeleev is hydrogen, not carbon.
63 elements were in Dmitri Mendeleev's First periodic table 63 elements were in Dmitri Mendeleev's First periodic table
=== ===Dmitri Mendeleev was a Russian chemist who formulated the periodic table.