Solutions

Introduction

• Importance of solutions is highlighted.
• Key terms: solute and solvent.

Basic Concepts

• Solution consists of a solute dissolved in a solvent (e.g., sugar in milk, salt in lemonade).
• Solvent is the major component; solute is the minor component.

Representation of Solutions

• Solutions can be represented in different measures (grams, liters, volumes).
• Concentrations are expressed based on the proportion of solute to solvent.

Important Definitions

• Solute: The substance that is dissolved.
• Solvent: The medium that dissolves the solute.
• Volume of Solution: Contains specific amounts of solute and solvent.

Solubility and Saturation

• Solubility varies with temperature and pressure conditions.
• Saturated Solution: Holds the maximum amount of solute under given conditions.

Vapor Pressure

• Solutions have a vapor pressure, derived from the solvent and solute interaction.
• Boiling Point Elevation: When a solute increases the boiling point of a solution.
• Raoult's Law: Describes the vapor pressure of an ideal solution.

Colligative Properties

• Depend on the number of solute particles, not their nature.
• Examples: Boiling point elevation, freezing point depression, osmotic pressure.

Osmotic Pressure

• Osmosis: Movement of solvent molecules through a semipermeable membrane from a lower to higher solute concentration.
• Osmotic Pressure: The pressure required to stop osmosis.
• Reverse Osmosis: Applying pressure to reverse the direction of osmosis.

Application of Colligative Properties

• Used to determine molecular weights and purity of compounds.

Additional Miscellaneous Points

• Solutions can be measured by molarity, molality, volume percent, etc.
• Isotonic Solutions: Two solutions with the same osmotic pressure.

Summary

• Solutions are an important part of chemistry with wide-ranging applications.
• Key focus on how solutes and solvents interact to form various types of solutions and their respective properties.

Important Formulas

• Raoult's Law: P_solution = Χ_solvent P⁰_solvent
• Boiling Point Elevation: ΔTb = i * Kb * m
• Freezing Point Depression: ΔTf = i * Kf * m
• Osmotic Pressure: π = iMRT