Question

As per the modern periodic law, the physical and chemical properties of elements are periodic functions of their:
This question has multiple correct options
(A) Atomic number
(B) Electronic configuration
(C) Atomic weight
(D) Atomic size

Answer 1

Hint: Out of the atomic number, electronic configuration, atomic size and atomic weight, determine which properties are fundamental to the physical and chemical properties of the elements. Also determine which of the above properties are responsible for the periodic properties of the elements.

Complete answer:
In the modern periodic table, the elements are arranged in the increasing order of their atomic numbers. The electronic configuration of an atom is directly related to its atomic number. Hence, you can say that the arrangement of the elements in the modern periodic table is also based on their electronic configuration.
You can observe that when elements are arranged in the increasing order of atomic number, certain periodic trends are observed in the physical and chemical properties.
In a group, the elements have similar valence shell electronic configuration. Also, the elements in a group have similar physical and chemical properties.
As per the modern periodic law, the physical and chemical properties of elements are periodic functions of their atomic number and electronic configuration.

Hence, the correct options are the options (A) and (B).

Note: In earlier attempts of periodic classification of the elements, instead of atomic number, people used atomic weight as the basis of classification. Thus, according to the periodic law of Mendeleev, the physical and chemical properties of elements are periodic functions of their atomic mass.