The periodic classification is an arrangement of the elements

A.

atomic weights

B.

isotopic weights

C.

molecular weights

D.

atomic numbers

Correct answer is D

Elements in the periodic table are arranged according to their atomic number (proton number). Electronegativity increase from left to right while atomic radius increases down the group

Elements in the periodic table are arranged according to their atomic number (proton number). Electronegativity increase from left to right while atomic radius increases down the group