Chapter 8, Problem 49P

Use the solubility rules listed in Section 8.3B to predict whether each of the following ionic compounds is soluble in water.

1. ${\text{K}}_{\text{2}}{\text{SO}}_{\text{4}}$

${\text{MgSO}}_{\text{4}}$

${\text{ZnCO}}_{\text{3}}$

$\text{KI}$

${\text{Fe(NO}}_3{\text{)}}_3$

${\text{PbCl}}_{\text{2}}$

${\text{CsCl}}_{\text{2}}$

${\text{Ni(HCO}}_{\text{3}}{)}_2$

Interpretation Introduction

(a)

Interpretation:

Whether ${\text{K}}_{\text{2}}{\text{SO}}_4$ is soluble in water or not should be identified.

Concept introduction:

The criteria to determine the solubility of a given solute in a particular solvent is governed by the principle of like dissolves like which means that the polar solvents such as water and alcohols tend to dissolve polar compounds while the non-polar solvents like hexane and urea dissolve covalent or non-polar compounds. Several forces are responsible for solubility of various compounds. For example, the sodium chloride solution is held by electrostatic forces of interaction. Polar molecules such as ethanol that are uncharged dissolved in water via hydrogen bonding interactions.

Water is a polar solvent as it contains highly electronegative oxygen atom and electropositive hydrogen atoms. Therefore, the ionic solids and some polar molecules which are relatively small can dissolve in water.

Answer to Problem 49P

  ${\text{K}}_{\text{2}}{\text{SO}}_4$ is soluble in water.

Explanation of Solution

The solubility of ionic solids is controlled by two basic principles as follows:

1. The compound that consists of group IA cations that include either of the ions ${\text{Li}}^{+}{\text{/Na}}^{+}{\text{/K}}^{+}{\text{/Rb}}^{+}{\text{/Cs}}^{+}$ or ${\text{NH}}_4{}^{+}$ ion is soluble in water.

2.The compound that consists of ${\text{NO}}_3{}^{-}$ , acetate, sulphate, or halides such as ${\text{Cl}}^{-}/{\text{Br}}^{-}/{\text{I}}^{-}$ are also soluble in water.

Since ${\text{K}}_{\text{2}}{\text{SO}}_4$ contains ${\text{K}}^{+}$ ion that belongs to group IA cations and as all potassium salts are soluble. In addition to this, sulphates are also soluble hence ${\text{K}}_{\text{2}}{\text{SO}}_4$ is soluble in water.

Interpretation Introduction

(b)

Interpretation:

Whether ${\text{MgSO}}_4$ is soluble in water or not should be identified.

Concept introduction:

The criteria to determine the solubility of a given solute in a particular solvent is governed by the principle of like dissolves like which means that the polar solvents such as water and alcohols tend to dissolve polar compounds while the non-polar solvents like hexane and urea dissolve covalent or non-polar compounds. Several forces are responsible for solubility of various compounds. For example, the sodium chloride solution is held by electrostatic forces of interaction. Polar molecules such as ethanol that are uncharged dissolved in water via hydrogen bonding interactions.

Water is a polar solvent as it contains highly electronegative oxygen atom and electropositive hydrogen atoms. Therefore, the ionic solids and some polar molecules which are relatively small can dissolve in water.

Answer to Problem 49P

  ${\text{MgSO}}_4$ is insoluble in water.

Explanation of Solution

The solubility of ionic solids is controlled by two basic principles as follows:

1. The compound that consists of group IA cations that include either of the ions ${\text{Li}}^{+}{\text{/Na}}^{+}{\text{/K}}^{+}{\text{/Rb}}^{+}{\text{/Cs}}^{+}$ or ${\text{NH}}_4{}^{+}$ ion is soluble in water.

2.The compound that consists of ${\text{NO}}_3{}^{-}$ , acetate, sulphate, or halides such as ${\text{Cl}}^{-}/{\text{Br}}^{-}/{\text{I}}^{-}$ are also soluble in water.

Since ${\text{MgSO}}_4$ contains ${\text{Mg}}^{2+}$ ion that belongs to group II cations hence ${\text{MgCO}}_3$ is insoluble in water.

Though the cationic species can interact via electrostatic interaction with the water dipole, however water cannot break the strong interionic forces between ${\text{Mg}}^{2+}$ and the ${\text{SO}}_4{}^{2-}$ ion and hence cannot dissolve magnesium sulphate into it.

Interpretation Introduction

(c)

Interpretation:

Whether ${\text{ZnCO}}_3$ is soluble in water or not should to be identified.

Concept introduction:

The criteria to determine the solubility of a given solute in a particular solvent is governed by the principle of like dissolves like which means that the polar solvents such as water and alcohols tend to dissolve polar compounds while the non-polar solvents like hexane and urea dissolve covalent or non-polar compounds. Several forces are responsible for solubility of various compounds. For example, the sodium chloride solution is held by electrostatic forces of interaction. Polar molecules such as ethanol that are uncharged dissolved in water via hydrogen bonding interactions.

Water is a polar solvent as it contains highly electronegative oxygen atom and electropositive hydrogen atoms. Therefore, the ionic solids and some polar molecules which are relatively small can dissolve in water.

Answer to Problem 49P

  ${\text{ZnCO}}_3$ is insoluble in water.

Explanation of Solution

The solubility of ionic solids is controlled by two basic principles as follows:

1. The compound that consists of group IA cations that include either of the ions ${\text{Li}}^{+}{\text{/Na}}^{+}{\text{/K}}^{+}{\text{/Rb}}^{+}{\text{/Cs}}^{+}$ or ${\text{NH}}_4{}^{+}$ ion is soluble in water.

2.The compound that consists of ${\text{NO}}_3{}^{-}$ , acetate, sulphate, or halides such as ${\text{Cl}}^{-}/{\text{Br}}^{-}/{\text{I}}^{-}$ are also soluble in water.

The ionic compound ${\text{ZnCO}}_3$ is insoluble as the equilibrium is largely towards the undissociated ${\text{ZnCO}}_3$ given as follows:

  ${\text{ZnCO}}_3\left(s\right)\rightleftharpoons {\text{Zn}}^{2+}\left(aq\right)+{\text{CO}}_3{}^{2-}\left(l\right)$

Further ${\text{Zn}}^{2+}$ do not belong to the category of group IA cations so it is not soluble in water.

Interpretation Introduction

(d)

Interpretation:

Whether $\text{KI}$ is soluble in water or not shouldbe identified.

Concept introduction:

The criteria to determine the solubility of a given solute in a particular solvent is governed by the principle of like dissolves like which means that the polar solvents such as water and alcohols tend to dissolve polar compounds while the non-polar solvents like hexane and urea dissolve covalent or non-polar compounds. Several forces are responsible for solubility of various compounds. For example, the sodium chloride solution is held by electrostatic forces of interaction. Polar molecules such as ethanol that are uncharged dissolved in water via hydrogen bonding interactions.

Water is a polar solvent as it contains highly electronegative oxygen atom and electropositive hydrogen atoms. Therefore, the ionic solids and some polar molecules which are relatively small can dissolve in water.

Answer to Problem 49P

  $\text{KI}$ is soluble in water.

Explanation of Solution

The solubility of ionic solids is controlled by two basic principles as follows:

1. The compound that consists of group IA cations that include either of the ions ${\text{Li}}^{+}{\text{/Na}}^{+}{\text{/K}}^{+}{\text{/Rb}}^{+}{\text{/Cs}}^{+}$ or ${\text{NH}}_4{}^{+}$ ion is soluble in water.

2.The compound that consists of ${\text{NO}}_3{}^{-}$ , acetate, sulphate, or halides such as ${\text{Cl}}^{-}/{\text{Br}}^{-}/{\text{I}}^{-}$ are also soluble in water.

Since $\text{KI}$ contains ${\text{K}}^{+}$ ion that belongs to group IA cations and as all potassium salts are soluble. In addition to this,iodides are also soluble and hence $\text{KI}$ is soluble in water.

Interpretation Introduction

(e)

Interpretation:

Whether $\text{Fe}{\left({\text{NO}}_3\right)}_2$ is soluble in water or not shouldbe identified.

Concept introduction:

The criteria to determine the solubility of a given solute in a particular solvent is governed by the principle of like dissolves like which means that the polar solvents such as water and alcohols tend to dissolve polar compounds while the non-polar solvents like hexane and urea dissolve covalent or non-polar compounds. Several forces are responsible for solubility of various compounds. For example, the sodium chloride solution is held by electrostatic forces of interaction. Polar molecules such as ethanol that are uncharged dissolved in water via hydrogen bonding interactions.

Water is a polar solvent as it contains highly electronegative oxygen atom and electropositive hydrogen atoms. Therefore, the ionic solids and some polar molecules which are relatively small can dissolve in water.

Answer to Problem 49P

  $\text{Fe}{\left({\text{NO}}_3\right)}_2$ is soluble in water.

Explanation of Solution

The solubility of ionic solids is controlled by two basic principles as follows:

1. The compound that consists of group IA cations that include either of the ions ${\text{Li}}^{+}{\text{/Na}}^{+}{\text{/K}}^{+}{\text{/Rb}}^{+}{\text{/Cs}}^{+}$ or ${\text{NH}}_4{}^{+}$ ion is soluble in water.

2.The compound that consists of ${\text{NO}}_3{}^{-}$ , acetate, sulphate, or halides such as ${\text{Cl}}^{-}/{\text{Br}}^{-}/{\text{I}}^{-}$ are also soluble in water.

The ionic compound $\text{Fe}{\left({\text{NO}}_3\right)}_2$ is soluble and dissociates to give ${\text{Fe}}^{3+}$ and ${\text{NO}}_3{}^{-}$ as follows:

  $\text{Fe}{\left({\text{NO}}_3\right)}_2\left(s\right)\to {\text{Fe}}^{3+}\left(aq\right)+{\text{NO}}_3{}^{-}\left(l\right)$

Since $\text{Fe}{\left({\text{NO}}_3\right)}_2$ contains ${\text{Fe}}^{3+}$ cation and ${\text{NO}}_3{}^{-}$ anion. Although ${\text{Fe}}^{3+}$ salts are not soluble however the salts that contain ${\text{NO}}_3{}^{-}$ anion are water-soluble as per the solubility rules and therefore, $\text{Fe}{\left({\text{NO}}_3\right)}_2$ is water-soluble.

Interpretation Introduction

(f)

Interpretation:

Whether ${\text{PbCl}}_2$ is soluble in water or not shouldbe identified.

Concept introduction:

The criteria to determine the solubility of a given solute in a particular solvent is governed by the principle of like dissolves like which means that the polar solvents such as water and alcohols tend to dissolve polar compounds while the non-polar solvents like hexane and urea dissolve covalent or non-polar compounds. Several forces are responsible for solubility of various compounds. For example, the sodium chloride solution is held by electrostatic forces of interaction. Polar molecules such as ethanol that are uncharged dissolved in water via hydrogen bonding interactions.

Water is a polar solvent as it contains highly electronegative oxygen atom and electropositive hydrogen atoms. Therefore, the ionic solids and some polar molecules which are relatively small can dissolve in water.

Answer to Problem 49P

  ${\text{PbCl}}_2$ is insoluble in water.

Explanation of Solution

The solubility of ionic solids is controlled by two basic principles as follows:

1. The compound that consists of group IA cations that include either of the ions ${\text{Li}}^{+}{\text{/Na}}^{+}{\text{/K}}^{+}{\text{/Rb}}^{+}{\text{/Cs}}^{+}$ or ${\text{NH}}_4{}^{+}$ ion is soluble in water.

2.The compound that consists of ${\text{NO}}_3{}^{-}$ , acetate, sulphate, or halides such as ${\text{Cl}}^{-}/{\text{Br}}^{-}/{\text{I}}^{-}$ are also soluble in water.

Since ${\text{PbCl}}_2$ contains ${\text{Pb}}^{2+}$ cation and ${\text{Cl}}^{-}$ anion. Although ${\text{Pb}}^{2+}$ salts are not soluble even when the halides such as ${\text{Cl}}^{-}$ anion are present, and therefore, ${\text{PbCl}}_2$ is water-insoluble.

Interpretation Introduction

(g)

Interpretation:

Whether $\text{CsCl}$ is soluble in water or not should be identified.

Concept introduction:

The criteria to determine the solubility of a given solute in a particular solvent is governed by the principle of like dissolves like which means that the polar solvents such as water and alcohols tend to dissolve polar compounds while the non-polar solvents like hexane and urea dissolve covalent or non-polar compounds. Several forces are responsible for solubility of various compounds. For example, the sodium chloride solution is held by electrostatic forces of interaction. Polar molecules such as ethanol that are uncharged dissolved in water via hydrogen bonding interactions.

Water is a polar solvent as it contains highly electronegative oxygen atom and electropositive hydrogen atoms. Therefore, the ionic solids and some polar molecules which are relatively small can dissolve in water.

Answer to Problem 49P

  $\text{CsCl}$ is soluble in water.

Explanation of Solution

The solubility of ionic solids is controlled by two basic principles as follows:

1. The compound that consists of group IA cations that include either of the ions ${\text{Li}}^{+}{\text{/Na}}^{+}{\text{/K}}^{+}{\text{/Rb}}^{+}{\text{/Cs}}^{+}$ or ${\text{NH}}_4{}^{+}$ ion is soluble in water.

2.The compound that consists of ${\text{NO}}_3{}^{-}$ , acetate, sulphate, or halides such as ${\text{Cl}}^{-}/{\text{Br}}^{-}/{\text{I}}^{-}$ are also soluble in water.

Since $\text{CsCl}$ contains $\text{Cs}$ cation and ${\text{Cl}}^{-}$ anion. All cesium salts are soluble and further salts that contain ${\text{Cl}}^{-}$ anion are water-soluble, and therefore, $\text{CsCl}$ is water-soluble.

Interpretation Introduction

(h)

Interpretation:

Whether $\text{Ni}{\left({\text{HCO}}_{\text{3}}\right)}_2$ is soluble in water or not should be identified.

Concept introduction:

The criteria to determine the solubility of a given solute in a particular solvent is governed by the principle of like dissolves like which means that the polar solvents such as water and alcohols tend to dissolve polar compounds while the non-polar solvents like hexane and urea dissolve covalent or non-polar compounds. Several forces are responsible for solubility of various compounds. For example, the sodium chloride solution is held by electrostatic forces of interaction. Polar molecules such as ethanol that are uncharged dissolved in water via hydrogen bonding interactions.

Water is a polar solvent as it contains highly electronegative oxygen atom and electropositive hydrogen atoms. Therefore, the ionic solids and some polar molecules which are relatively small can dissolve in water.

Answer to Problem 49P

  $\text{Ni}{\left({\text{HCO}}_{\text{3}}\right)}_2$ is insoluble in water.

Explanation of Solution

The solubility of ionic solids is controlled by two basic principles as follows:

1. The compound that consists of group IA cations that include either of the ions ${\text{Li}}^{+}{\text{/Na}}^{+}{\text{/K}}^{+}{\text{/Rb}}^{+}{\text{/Cs}}^{+}$ or ${\text{NH}}_4{}^{+}$ ion is soluble in water.

2.The compound that consists of ${\text{NO}}_3{}^{-}$ , acetate, sulphate, or halides such as ${\text{Cl}}^{-}/{\text{Br}}^{-}/{\text{I}}^{-}$ are also soluble in water.

Since $\text{Ni}{\left({\text{HCO}}_{\text{3}}\right)}_2$ contains ${\text{Ni}}^{2+}$ cation and ${\text{HCO}}_{\text{3}}{}^{-}$ anion. All nickel salts are not usually soluble and further salts contain nickel salts or salts of metals other than contains sodium that ${\text{HCO}}_{\text{3}}{}^{-}$ anion are water-insoluble, and therefore, $\text{Ni}{\left({\text{HCO}}_{\text{3}}\right)}_2$ is water-insoluble.