Chapter 7, Problem 54A

Interpretation Introduction

Interpretation: The relationship between the electron dot structure of an element and its location in the periodic table needs to be explained.

Concept Introduction: Electron dot structures of an atom of an element represent the number of electron/s present in its valance electron shell. In the electron dot structure, the symbol of an atom of an element is written and the number of valance electrons is arranged in pairs represented as dots around the symbol.

For example, the number of valance electrons in a bromine atom is 7; thus, its electron dot structure is represented as follows:

  

Explanation of Solution

Elements are arranged in the periodic table in increasing order of their atomic numbers. There are groups and periods in the periodic table. Group number indicates the number of valence electrons in an atom. Here, the atomic number of an element is equal to the number of electrons present in its atom.

The electrons are present in the atomic orbitals of an atom. The electron configuration of an atom shows the distribution of electrons in the atomic orbitals. Here, electrons present in the valence shell are known as valence electrons. The electron dot structure is used to represent these valence electrons.

Thus, from an electron dot structure, the valence electrons of an atom can be identified and if the number of valence electrons of an atom is known, its group number can be identified and so its position in the periodic table.

Thus, there is a relationship between electron dot structure and the position of an element in the periodic table.