Chapter 4, Problem 4.1KSP

Interpretation Introduction

Interpretation:

It should be determined the group that exhibits highest second ionization energy.

Concept introduction:

First ionization energy:  It is the amount of energy required to remove one electron from a neutral atom.

Second ionization energy: It is the amount of energy required to remove another electron from an ion.

Answer to Problem 4.1KSP

The given option e is the correct answer

Explanation of Solution

Reason for the correct answer

For expalining the reason for correct answer it is needed to take one element from the group 1A Sodium (Na) is taken as an example

Atomic number of sodium is 11 and elelctronic configuration can be written as follows;

${\text{1s}}^{\text{2,}}{\text{2s}}^{\text{2}}\text{,}{\text{2p}}^{\text{6}}\text{,}{\text{3s}}^{\text{1}}$

The first ionisation energy is the amount of energy required to remove one electron from a neutral atom.  So the one electron can be easily removed from the ${\text{3s}}^{\text{1}}$

By removing the one electron from the outermost shell, Sodium ion is formed and the electronic configuration becomes,

${\text{Na}}^{+}{\text{;1s}}^{\text{2,}}{\text{2s}}^{\text{2}}\text{,}{\text{2p}}^{\text{6}}$

Second ionization energy is the amount of energy required to remove another electron from an ion.

Here in the case the electronic configuration can be written as

${\text{Na}}^{+}\text{;}\text{2,8}$

According octet rule it attains eight electrons in the outer most shell.  So it is very difficult to remove one single electron from the ion.  That is more energy is required to remove the electron from the ion.  So it can be concluded that group 1A exhibits the highest second ionization energy.

Reason for incorrect answer

Since the electronic configuration of elements from the group 1A after removing the single electron attains the eight electrons, it is very difficult to remove another electron from an ion and higher amount of energy is required.

Conclusion

The group that exhibits highest second ionization energy was determined.