Chapter 8.4, Problem 8.7AFP

(a)

Interpretation Introduction

Interpretation:

${\text{Cl}}^{-}$, ${\text{Br}}^{-}$ and ${\text{F}}^{-}$ are to be arranged in the order of increasing size.

Concept introduction:

The cation is an ionic species with a positive charge. It has more protons as compared to electrons so the net charge on the cations is positive. Its symbol is the element with a superscript of the positive charge.

The anion is an ionic species with a negative charge. It has more electrons than protons so the net charge on the anions is negative. Its symbol is the element with a superscript of the negative charge.

In general, cations are smaller than anions because the number of shells decreases after the loss of electrons in case of cations.

In the case of isoelectronic species, the size of cations decreases with an increase in positive charge and size of anion increases with an increase in a negative charge.

(b)

Interpretation Introduction

Interpretation:

${\text{Na}}^{+}$, ${\text{Mg}}^{2+}$, and ${\text{F}}^{-}$ are to be arranged in the order of the increasing size.

Concept introduction:

The cation is an ionic species with a positive charge. It has more protons as compared to electrons so the net charge on the cations is positive. Its symbol is the element with a superscript of the positive charge.

The anion is an ionic species with a negative charge. It has more electrons than protons so the net charge on the anions is negative. Its symbol is the element with a superscript of the negative charge.

In general, cations are smaller than anions because the number of shells decreases after the loss of electrons in case of cations.

In the case of isoelectronic species, the size of cations decreases with an increase in positive charge and size of anion increases with an increase in a negative charge.

(c)

Interpretation Introduction

Interpretation:

${\text{Cr}}^{2+}$ and ${\text{Cr}}^{3+}$ are to be arranged in the order of the increasing size.

Concept introduction:

The cation is an ionic species with a positive charge. It has more protons as compared to electrons so the net charge on the cations is positive. Its symbol is the element with a superscript of the positive charge.

The anion is an ionic species with a negative charge. It has more electrons than protons so the net charge on the anions is negative. Its symbol is the element with a superscript of the negative charge.

In general, cations are smaller than anions because the number of shells decreases after the loss of electrons in case of cations.

In the case of isoelectronic species, the size of cations decreases with an increase in positive charge and size of anion increases with an increase in a negative charge.