Question

Identify the type of interactions involved in each of the following processes taking place during the dissolution of sodium chloride (NaClNaCl) in water.
I. Solvent-solvent interactions
II. Solute-solute interactions
III. Solute-solvent interactions

A. Interactions between the ions of sodium chloride
B. Interactions involving dipole-dipole attractions
C. Interactions formed during hydration
D. Interactions involving ion-ion attractions
E. Interactions associated with an exothermic process during the dissolution of sodium chloride
F. Interactions between the water molecules
G. Interactions formed between the sodium ions and the oxygen atoms of water molecules

Please match which letters match to their designated interaction type.

Answer 1

Answer:

I. Solvent-solvent interactions  ⇒ B, F

II. Solute-solute interactions  ⇒ A, D

III. Solute-solvent interactions ⇒ C, E, G

Explanation:

In the dissolution of sodium chloride (NaCl) in water, the solute is NaCl which in solution is dissociated into its ions (Na⁺ and Cl⁻) and the solvent is water (H₂O) whose molecules are polar and therefore are considered as dipoles.

Solvent-solvent interactions are between water molecules so they are between dipoles (options B and F)

Solute-solute interactions are between NaCl ions in which electrostatic forces are involved. They can be between sodium ions or choride iones (Na⁺-Na⁺, Cl⁻-Cl⁻, repulsive) or between sodium and chloride ions (Na⁺-Cl⁻, attractive) (options A and D).

Solute-solvent interactions are between sodium chloride ions and water molecules, so dipole-ion forces are involved. During dissolution process, solute ions are surrounded by water molecules, which is called hydration. The overall process is exothermic (releases heat) (options C, E and G).