Chapter 5, Problem 94QRT

Interpretation Introduction

Interpretation:

Thegroup of the periodic table in which elements have high first ionization energy and very negative electron affinity has to be explained.

Concept Introduction:

Ionization energy: It is the energy needed to remove an electron from that atom in gas phase.  For a gaseous sodium atom, the ionization process is given as,

    ${\text{Na}}_{\text{(g)}}\underset{}{\overset{}{\to }}{\text{Na}}^{\text{+}}{}_{\text{(g)}}\text{+}{\text{e}}^{\text{-}}$

Electron affinity:  It is the energy change when an electron is added to a gaseous atom to form $-1$ ion.  Also, it is a measure of the attraction an atom has for an additional electron.  Eg: electron affinity of fluorine is $\text{-328kJ/mol}$

    ${\text{F}}_{\text{(g)}}\text{+}{\text{e}}^{\text{-}}\underset{}{\overset{}{\to }}{\text{F}}^{\text{-}}{}_{\text{(g)}}$