Chem 2 Chapter 13 Questions part 1

A favorable process in solution formation involves a release of heat (exothermic) and an increase in disorder (increasing entropy).

The formation of attractions between solute and solvent molecules is always a process that releases energy.

A solution can still form even with energy input (endothermic) if there is a significant increase in disorder (large positive entropy change).

The main factor determining if a solute dissolves in a solvent is the similarity in their intermolecular forces. This is known as the 'like dissolves like' principle.

NaCl (ionic) is best dissolved in water (polar) because both have strong dipole-dipole interactions.

London Dispersion Forces (LDF) are the weakest intermolecular force and dominate in nonpolar substances.

Oil, being nonpolar, cannot form strong interactions with water, which is polar. This prevents mixing.

Dynamic equilibrium in solution formation means there's a constant balance between solute dissolving and crystallizing out of the solution.

The solubility product constant (Ksp) represents the equilibrium constant for the dissolution of an ionic solid in water. It indicates how much of the solute dissolves in solution.

A high Ksp value indicates a high solubility of the ionic compound in water - more of it dissolves.

Pressure increases the solubility of gases in liquids. More gas molecules are forced into the solution under higher pressure.

Increasing temperature usually increases the solubility of solids because it provides more energy for breaking intermolecular forces.

Gases become less soluble at higher temperatures because the gas molecules gain kinetic energy and escape the liquid more easily.

The presence of a catalyst does not affect solubility. Catalysts only speed up the rate of a reaction, not the amount of substance dissolved.

The common ion effect decreases the solubility of a sparingly soluble salt in water.

A supersaturated solution contains more dissolved solute than its solubility allows at a given temperature. This is an unstable state.

Higher entropy generally favors solubility because it allows more freedom of movement for the solute and solvent molecules.

The solute molecules are nonpolar and the solvent molecules are polar, leading to weak interactions.

Adding a common ion (same type of ion) to a saturated solution decreases solubility because it shifts the equilibrium to favor precipitation.

Ionic compounds dissolve in water primarily due to ion-dipole interactions. Water's polarity attracts the charged ions, breaking the ionic lattice.

Lowering the temperature generally decreases the solubility of gases in liquids because the gas molecules have less energy to stay dissolved.

Freezing point depression is a colligative property, meaning it's affected by the number of solute particles dissolved.

Increasing solute concentration raises the boiling point of a solution. This is because the solute particles interfere with the vapor pressure of the solvent.

Osmotic pressure is the pressure that needs to be applied to a solution to prevent the inward flow of solvent across a semipermeable membrane.

Increasing the number of solute particles lowers the freezing point of the solution. This is because the solute particles disrupt the formation of the solvent's solid structure.

Raoult's Law states that the vapor pressure of an ideal solution is directly proportional to the mole fraction of the solvent.

Increasing temperature increases vapor pressure. The molecules have more energy to escape and form a vapor.

A saturated solution contains the maximum amount of solute that can dissolve at a given temperature, at equilibrium.

A supersaturated solution contains more dissolved solute than its solubility allows at a given temperature, a metastable state.

Colligative properties are properties of solutions that depend on the number of solute particles present, not the identity of the solute.