Chapter 12, Problem 106E

(a)

Interpretation Introduction

Interpretation: Out of atoms $\text{H}$ and $\text{He}$ one with smaller radius should be identified.

Concept introduction: As one moves from top to bottom the shells expands and size increases, while it decreases as one move along the period because of gradual increases in effective nuclear charge. This in turn increases influence of nucleus on valence electron and shrinks the radius along the horizontal row.

(b)

Interpretation Introduction

Interpretation: Out of atoms $\text{Cl}$ , $\text{In}$ and $\text{Se}$ one with smallest radius should be identified.

Concept introduction: As one moves from top to bottom the shells expands and size increases, while it decreases as one move along the period because of gradual increases in effective nuclear charge. This in turn increases influence of nucleus on valence electron and shrinks the radius along the horizontal row.

(c)

Interpretation Introduction

Interpretation: Out of elements with atomic numbers 120, 119, 117 one with smallest radius should be identified.

Concept introduction: As one moves from top to bottom the shells expands and size increases, while it decreases as one move along the period because of gradual increases in effective nuclear charge. This in turn increases influence of nucleus on valence electron and shrinks the radius along the horizontal row.

(d)

Interpretation Introduction

Interpretation: Out of atoms $\text{Nb}$ , $\text{Zn}$ and $\text{Si}$ one with smallest radius should be identified.

Concept introduction: As one moves from top to bottom the shells expands and size increases, while it decreases as one move along the period because of gradual increases in effective nuclear charge. This in turn increases influence of nucleus on valence electron and shrinks the radius along the horizontal row.

(e)

Interpretation Introduction

Interpretation: Of atoms ${\text{Na}}^{-}$ , $\text{Na}$ and ${\text{Na}}^{+}$ one with smallest radius should be identified.

Concept introduction: As one moves from top to bottom the shells expands and size increases, while it decreases as one move along the period because of gradual increases in effective nuclear charge. This in turn increases influence of nucleus on valence electron and shrinks the radius along the horizontal row.