Chapter 5.3, Problem 6E

(a)

Interpretation Introduction

Interpretation: The solubility of ${\text{C}}_{\text{6}}{\text{H}}_{\text{5}}{\text{CO}}_{\text{2}}\text{Na}$ in organic solvent or water needs to be explained.

Concept Introduction:A solution is a mixture of solute and solvent. The solubility of solute in solvent depends on the interaction between solute and solvent. It also depends on the polarity of molecules also. As the polar and ionic compounds are soluble in polar solvents whereas the non-polar compounds are soluble in non-polar solvents such as organic solvents. Therefore, it is said to be “Like dissolves Like”.

Answer to Problem 6E

  ${\text{C}}_{\text{6}}{\text{H}}_{\text{5}}{\text{CO}}_{\text{2}}\text{Na}$ is soluble in water as it is ionic salt of benzoic acid.

Explanation of Solution

  ${\text{C}}_{\text{6}}{\text{H}}_{\text{5}}{\text{CO}}_{\text{2}}\text{Na}$ is an ionic compound as it is salt of benzoic acid and sodium hydroxide. Since ionic compounds are soluble due to formation of ions which can easily attract towards dipole water molecule.

  ${\text{C}}_{\text{6}}{\text{H}}_{\text{5}}{\text{CO}}_{\text{2}}\text{Na}\stackrel{}{\to }{\text{C}}_{\text{6}}{\text{H}}_{\text{5}}{\text{CO}}_{{}_{\text{2}}}^{\text{-}}{\text{+ Na}}^{\text{+}}$

(b)

Interpretation Introduction

Interpretation: The solubility of naphthalene in organic solvent or water needs to be explained.

Concept Introduction:A solution is a mixture of solute and solvent. The solubility of solute in solvent depends on the interaction between solute and solvent. It also depends on the polarity of molecules also. As the polar and ionic compounds are soluble in polar solvents whereas the non-polar compounds are soluble in non-polar solvents such as organic solvents. Therefore, it is said to be “Like dissolves Like”.

Answer to Problem 6E

Naphthalene is soluble in organic solvent as it is a non-polar compound.

Explanation of Solution

Naphthalene is an aromatic hydrocarbon which is composed of C and H atoms. The structural formula of naphthalene can be shown as below:

  

Since there is no other functional group in the molecule,therefore, it is a non-polar molecule and is soluble in a non-polar solvent.

(c)

Interpretation Introduction

Interpretation: The solubility of Anthracenein organic solvent or water needs to be explained.

Concept Introduction:A solution is a mixture of solute and solvent. The solubility of solute in solvent depends on the interaction between solute and solvent. It also depends on the polarity of molecules also. As the polar and ionic compounds are soluble in polar solvents whereas the non-polar compounds are soluble in non-polar solvents such as organic solvents. Therefore, it is said to be “Like dissolves Like”.

Answer to Problem 6E

Anthracene is soluble in organic solvent as it is a non-polar compound.

Explanation of Solution

Anthracene is an aromatic hydrocarbon which is composed of C and H atoms. The structural formula of Anthracene can be shown as below:

  

Since there is no other functional group in the molecule therefore it is a non-polar molecule and is soluble in a non-polar solvent.

(d)

Interpretation Introduction

Interpretation: The solubility of phenolin organic solvent or water needs to be explained.

Concept Introduction:A solution is a mixture of solute and solvent. The solubility of solute in solvent depends on the interaction between solute and solvent. It also depends on the polarity of molecules also. The polar and ionic compounds are soluble in polar solvents, whereas the non-polar compounds are soluble in non-polar solvents such as organic solvents. Therefore, it is said to be “Like dissolves Like”.

Answer to Problem 6E

Phenol is soluble water as it is a polar compound.

Explanation of Solution

Phenol is an aromatic hydrocarbon which is composed of C and H atoms with −OH group. The structural formula of phenol can be shown as below:

  

The −OH group can form hydrogen bond with water molecule therefore it is soluble in water.

(e)

Interpretation Introduction

Interpretation: The solubility of ${\text{C}}_{\text{6}}{\text{H}}_{\text{5}}{\text{NH}}_{\text{2}}$ in organic solvent or water needs to be explained.

Concept Introduction:A solution is a mixture of solute and solvent. The solubility of solute in solvent depends on the interaction between solute and solvent. It also depends on the polarity of molecules also. The polar and ionic compounds are soluble in polar solvents, whereas, the non-polar compounds are soluble in non-polar solvents such as organic solvents. Therefore, it is said to be “Like dissolves Like”.

Answer to Problem 6E

  ${\text{C}}_{\text{6}}{\text{H}}_{\text{5}}{\text{NH}}_{\text{2}}$ is soluble in organic solvent.

Explanation of Solution

  ${\text{C}}_{\text{6}}{\text{H}}_{\text{5}}{\text{NH}}_{\text{2}}$ is an aromatic hydrocarbon which is composed of C and H atoms with −NH₂group. The structural formula of ${\text{C}}_{\text{6}}{\text{H}}_{\text{5}}{\text{NH}}_{\text{2}}$

can be shown as below:

  

  ${\text{C}}_{\text{6}}{\text{H}}_{\text{5}}{\text{NH}}_{\text{2}}$ is an aromatic compound with −NH₂group. Although it can form hydrogen bonding with water molecule, yet due to phenyl group, it is more soluble in organic solvent.

(f)

Interpretation Introduction

Interpretation: The solubility of $\text{NaCl}$ in organic solvent or water needs to be explained.

Concept Introduction:A solution is a mixture of solute and solvent. The solubility of solute in solvent depends on the interaction between solute and solvent. It also depends on the polarity of molecules also. The polar and ionic compounds are soluble in polar solvents, whereas, the non-polar compounds are soluble in non-polar solvents such as organic solvents. Therefore, it is said to be “Like dissolves Like”.

Answer to Problem 6E

  $\text{NaCl}$ is soluble in water as it is ionic salt.

Explanation of Solution

  $\text{NaCl}$ is an ionic compound as it is salt of benzoic acid and sodium hydroxide. Since ionic compounds are soluble due to formation of ions which can easily attract towards dipole water molecule.

(h)

Interpretation Introduction

Interpretation: The solubility of ${\text{CH}}_{\text{3}}{\text{CO}}_{\text{2}}\text{H}$ in organic solvent or water needs to be explained.

Concept Introduction:A solution is a mixture of solute and solvent. The solubility of solute in solvent depends on the interaction between solute and solvent. It also depends on the polarity of molecules also. The polar and ionic compounds are soluble in polar solvents, whereas, the non-polar compounds are soluble in non-polar solvents such as organic solvents. Therefore, it is said to be “Like dissolves Like”.

Answer to Problem 6E

  ${\text{CH}}_{\text{3}}{\text{CO}}_{\text{2}}\text{H}$ is soluble in water as it can form hydrogen bond with water.

Explanation of Solution

  ${\text{CH}}_{\text{3}}{\text{CO}}_{\text{2}}\text{H}$ is weak acid that is soluble water because it ionized in water and can also form hydrogen bond with water molecule that makes it soluble in water.

  ${\text{CH}}_{\text{3}}{\text{CO}}_{\text{2}}\text{H}\stackrel{}{\to }{\text{CH}}_{\text{3}}{\text{CO}}_{{}_{\text{2}}}^{\text{-}}{\text{+ H}}^{\text{+}}$