Chapter 9, Problem 72E

Interpretation Introduction

Interpretation: The number of elements present in periods 3 and 4 of the periodic table is to be listed. The difference that lies in these numbers is to be explained.

Concept Introduction: Elements are arranged in the order of increasing atomic number in periodic table.

From the periodic table, physical, chemical properties, electronic configuration of

the elements can be determined.

The principal quantum number $\left(n\right)$ specifies the principal shell of the orbital.

As the value of principal quantum number increases, the energy of the orbital also

increases.

The possible values of principal quantum number are 1, 2, 3….