Chapter 1, Problem 1F.5E

(a)

Interpretation Introduction

Interpretation:

Element having smaller first ionization energy has to be identified among $Ca,\text{ Mg}$.

Concept Introduction:

First ionization energy: The ionization energy is the minimum energy required to remove the electron from an isolated atom which is in the gaseous state results to give gaseous ion with one positive charge.

Down the group, generally first ionization energies decreases whereas across the period, first ionization energies typically increases.

(b)

Interpretation Introduction

Interpretation:

Element having smaller first ionization energy has to be identified among $\text{Mg},\text{ Na}$.

Concept Introduction:

Refer to (a).

(c)

Interpretation Introduction

Interpretation:

Element having smaller first ionization energy has to be identified among $\text{Al},\text{ Na}$.

Concept Introduction:

Refer to (a).