Solutions, Solubility, Thermochemistry Overview

What is a solution?

A homogeneous mixture of two or more substances.

Define solubility.

The maximum amount of solute that can dissolve in a given amount of solvent at a specific temperature.

What factors affect the solubility of a substance?

Temperature, pressure, and the nature of solute and solvent.

What is the solubility product constant (Ksp)?

The product of the concentrations of the ions of a sparingly soluble salt in a saturated solution.

What does it mean if a solution is supersaturated?

It contains more solute than what can be dissolved at a given temperature.

What is thermochemistry?

The study of heat changes that accompany chemical reactions and physical changes.

Define exothermic reaction.

A reaction that releases heat to the surroundings.

Define endothermic reaction.

A reaction that absorbs heat from the surroundings.

What is enthalpy (H)?

A measure of the total energy of a thermodynamic system.

What is the formula for calculating enthalpy change (ΔH)?

ΔH = H(products) - H(reactants).

What is the difference between a strong electrolyte and a weak electrolyte?

Strong electrolytes completely dissociate in solution, while weak electrolytes partially dissociate.

What is the significance of colligative properties?

Properties that depend on the number of solute particles in a solution, not their identity.

List four colligative properties.

Vapor pressure lowering, boiling point elevation, freezing point depression, and osmotic pressure.

What is the boiling point elevation equation?

ΔTb = i imes Kb imes m.

What is the freezing point depression equation?

ΔTf = i imes Kf imes m.

What does 'i' represent in colligative properties equations?

The van 't Hoff factor, representing the number of particles the solute breaks into.

What is the first law of thermodynamics?

Energy cannot be created or destroyed, only transformed.

Define specific heat capacity.

The amount of heat required to raise the temperature of 1 gram of a substance by 1 degree Celsius.

What is heat capacity?

The amount of heat needed to change the temperature of an object by 1 degree Celsius.

Define calorimetry.

The science of measuring the heat of chemical reactions or physical changes.

What is an isolated system?

A physical system that does not exchange matter or energy with its surroundings.

What is an open system?

A system that can exchange both matter and energy with its surroundings.

What is a closed system?

A system that can exchange energy but not matter with its surroundings.

What is Gibbs free energy (G)?

A thermodynamic potential that measures the maximum reversible work obtainable from a system.

What is the equation for Gibbs free energy change (ΔG)?

ΔG = ΔH - TΔS.

Define spontaneity in a chemical reaction.

A reaction is spontaneous if it occurs without external intervention.

What role does temperature play in solubility?

Generally, an increase in temperature increases solubility for solids and decreases it for gases.