The statement that is not correct for the periodic classification of elements is `:` a)The properties of elements are the periodic functions of their atomic numbers. b)non-metallic elements are lesser in number than metallic elements. c)the first ionisation energies of elements along a period do not vary in a regular manner with increase in atomic number. d)for transition elements the `d-` subshells are filled with electrons monotonically with increase in atomic number.

Options

A. the properties of elements are the periodic functions of their atomic numbers
B. non-metallic elements are lesser in number than metallic elements
C. the third period contains 8 elements and not 18 as 4th period contains
D. for transition elements the d-subshells are filled with electrons monotonically with increase in atomic number

Answer

D