Chapter 12, Problem 28A

(a)

Interpretation Introduction

Interpretation:

The species having small size is to be indicated.

Concept introduction:

Cations are always smaller than their parent atoms and anions are always larger than their parent atoms.

In periodic table, from left to right in a period size decreases and from top to bottom, size increases.

Answer to Problem 28A

  $\mathrm{M}{\mathrm{g}}^{2+}$

Explanation of Solution

  $\mathrm{M}{\mathrm{g}}^{2+}$ is smaller than $\mathrm{M}\mathrm{g}$ because cations are always smaller than their parent atoms.

(b)

Interpretation Introduction

Interpretation:

The species having small size is to be indicated.

Concept introduction:

Cations are always smaller than their parent atoms and anions are always larger than their parent atoms.

In periodic table, from left to right in a period size decreases and from top to bottom, size increases.

Answer to Problem 28A

  $\mathrm{C}{\mathrm{a}}^{2+}$

Explanation of Solution

  $\mathrm{C}{\mathrm{a}}^{2+}$ is smaller than ${\mathrm{K}}^{+}$ because in isoelectronic species, more the nuclear charge, smaller is the size.

Since, nuclear charge or number of protons/atomic number is more in Ca thus, it will be smaller in size.

(c)

Interpretation Introduction

Interpretation:

The species having small size is to be indicated.

Concept introduction:

Cations are always smaller than their parent atoms and anions are always larger than their parent atoms.

In periodic table, from left to right in a period size decreases and from top to bottom, size increases.

Answer to Problem 28A

  $\mathrm{B}{\mathrm{r}}^{-}$

Explanation of Solution

  $\mathrm{B}{\mathrm{r}}^{-}$ is smaller than $\mathrm{R}{\mathrm{b}}^{+}$ because bromine belongs to halogens and rubidium is alkali metal.

And alkali metals are largest in periodic table.

(d)

Interpretation Introduction

Interpretation:

The species having small size is to be indicated.

Concept introduction:

Cations are always smaller than their parent atoms and anions are always larger than their parent atoms.

In periodic table, from left to right in a period size decreases and from top to bottom, size increases.

Answer to Problem 28A

  $\mathrm{S}\mathrm{e}$

Explanation of Solution

  $\mathrm{S}\mathrm{e}$ is smaller than $\mathrm{S}{\mathrm{e}}^{2-}$ because anions are always larger than their parent atoms.