What happens when NaCl (aq) and H2O (l) interact? What types of intermolecular forces are operative, and is this a homogeneous solution? Is NaCl still intact as an ionic solid?

When sodium chloride (NaCl) is dissolved in water (H₂O), the process involves the breaking apart of the ionic compound into its constituent ions: Na⁺ and Cl^–. The water molecules, which are polar, interact with these ions through dipole-ion interactions.

The kind of intermolecular forces at play here include:

• Ion-Dipole Forces: These occur when the charged ions are surrounded by polar water molecules. The positive side of water molecules (hydrogen) is attracted to the chloride ions (Cl^–), while the negative side of water molecules (oxygen) is attracted to the sodium ions (Na⁺).
• Hydrogen Bonding: In pure water, hydrogen bonding occurs between water molecules. However, when NaCl is added, the presence of ions disrupts some of these interactions, but the overall hydrogen bonding network remains.

The solution formed is homogeneous because the NaCl disperses uniformly throughout the water. You can’t see the individual ions; they are evenly distributed in the solution, which is characteristic of a true solution.

When NaCl dissolves, it does not remain intact as an ionic solid. Instead, it dissociates into individual ions, which are free to move in the solution. Therefore, in the aqueous solution, NaCl is no longer an intact ionic solid but exists as Na⁺ and Cl^– ions surrounded by water molecules.