Chapter 26, Problem 110SAE

Interpretation Introduction

(a)

Interpretation:

Identify the compound with higher boiling point out of ${\text{C}}_{\text{6}}{\text{H}}_{\text{12}}{\text{ and C}}_{\text{2}}{\text{H}}_{\text{4}}$.

Concept introduction:

Boiling point is the temperature at which the liquid starts boiling. At this temperature the vapor pressure of liquid becomes equal to the atmospheric pressure. Boiling point of any substance depends on the structure, molecular weight and branching on the parent carbon chain of compound. As the branching on side chain increases, the boiling point decreases whereas it is increases with increasing the molecular mass of the substance. The presence of intermolecular force of attraction between molecules also effects the boiling point. If the molecules will strongly bonded with each other, the boiling point of it will be higher than the molecules with weak intermolecular force of attraction.

Interpretation Introduction

(b)

Interpretation:

Identify the compound with greater solubility in water out of $\text{C}\text{H}\text{O}\text{H and C}\text{H}{}_{\text{15}}\text{OH}$.

Concept introduction:

Alcohols are usually in water due to presence of polar −OH group. The presence of polar group in the molecule makes them soluble in polar solvents like water. Another reason of solubility of alcohols is the presence of hydrogen bonds between water and −OH group of alcohols. Since alcohols can form hydrogen bonding with water molecules therefore it increases the intermolecular force of attraction between molecules. That increases the solubility of alcohols.

Interpretation Introduction

(c)

Interpretation:

Identify the compound with greater acidity in aqueous solution out of ${\text{C}}_{\text{6}}{\text{H}}_{\text{5}}{\text{CHO and C}}_{\text{6}}{\text{H}}_{\text{5}}\text{COOH}$.

Concept introduction:

Aldehyde can be identified with the help of general formula R-CHO. The general formula of carboxylic acid is R-COOH. As the name suggested, it is acidic in nature due to its tendency to give H+ ions in aqueous solution.

${\text{RCOOH + H}}_{\text{2}}\text{O }\rightleftarrows {\text{ RCOO}}^{\text{-}}{\text{ + H}}_{\text{3}}{\text{O}}^{\text{+}}$

The ions formed in aqueous solution of carboxylic acid are called as carboxylate ions and hydronium ion.