Chapter 8.3, Problem 3PE

(a)

Interpretation Introduction

Interpretation: Smaller ion among $K^{+}$ and $L{i}^{+}$ has to be selected.

Concept Introduction:

Ionic radius is the distance between the atomic nucleus and outermost electron of an ion.

Down the group, the principal quantum number increases and thus the size of orbital also increases which results in the increase in atomic radii.

Group 1A in the periodic table contains 1 valence electrons and the outer electronic configuration is ${\text{ns}}^1$.

(b)

Interpretation Introduction

Interpretation: Smaller ion among $A{u}^{+}$ and $A{u}^{3+}$ has to be selected.

Concept Introduction:

Ionic radius is the distance between the atomic nucleus and outermost electron of an ion.

When an atom gets converted to a cation, the charge of nucleus remains the same while the number of electrons decreases. This decreases the repulsion and hence the electron cloud reduces which results in the decrease in ionic radius.

(c)

Interpretation Introduction

Interpretation: Smaller ion among $P^{3-}$ and $N^{3-}$ has to be selected.

Concept Introduction:

Ionic radius is the distance between the atomic nucleus and outermost electron of an ion.

Down the group, the principal quantum number increases and thus the size of orbital also increases which results in the increase in atomic radii.

Group 5A in the periodic table contains 5 valence electrons and the outer electronic configuration is ${\text{ns}}^{\text{2}}{\text{np}}^{\text{3}}$.