Which of the following is moderately soluble both in water...

Which of the following is moderately soluble both in water and in benzene, $\mathrm{C}_{6} \mathrm{H}_{6}(\mathrm{l}),$ and why? (a) 1 -butanol, $\mathrm{CH}_{3}\left(\mathrm{CH}_{2}\right)_{2} \mathrm{CH}_{2} \mathrm{OH} ;$ (b) naphthalene, $\mathrm{C}_{10} \mathrm{H}_{8} ;$ (c) hexane, $\mathrm{C}_{6} \mathrm{H}_{14} ;$ (d) $\mathrm{NaCl}(\mathrm{s})$.

Key Concepts

Hydrogen Bonding

Hydrogen bonding is a specific type of dipole-dipole interaction that occurs when a hydrogen atom is bonded to a highly electronegative atom, such as oxygen. In solutions, hydrogen bonding plays a crucial role in enhancing the solubility of molecules that contain hydroxyl groups in water, because water molecules can form hydrogen bonds with these functional groups.

Solvent-Solute Interactions

The principle of 'like dissolves like' is central to understanding solubility. It states that solutes tend to dissolve in solvents that are chemically similar (both in polarity and intermolecular forces). This concept, combined with the amphiphilic nature of some molecules, explains why a substance with both nonpolar and polar components can exhibit moderate solubility in both water and benzene.

Polarity

Polarity refers to the distribution of electrical charge over the atoms joined by the bond. In the context of solubility, compounds with polar functional groups tend to be more soluble in polar solvents like water, whereas nonpolar substances are more soluble in nonpolar solvents like benzene. The concept of polarity helps in understanding why certain molecules dissolve better in solvents that share a similar polarity.

Amphiphilicity

Amphiphilic molecules contain both polar (hydrophilic) and nonpolar (hydrophobic) parts. This dual nature enables them to interact with both water and organic solvents such as benzene. In compounds like 1-butanol, the hydroxyl group imparts polarity and the hydrocarbon chain provides nonpolar character, allowing moderate solubility in both types of solvents.

Transcript

Please give Ace some feedback