What Is A Solution

Key Notes:

Definition of a Solution

  • A solution is a homogeneous mixture composed of two or more substances.
  • In a solution, one substance is dissolved in another, resulting in a single phase.

Components of a Solution

  • Solvent: The substance that dissolves the solute. It is usually present in the largest amount (e.g., water in saltwater).
  • Solute: The substance that is dissolved in the solvent (e.g., salt in saltwater).

Characteristics of Solutions

  • Uniformity: Solutions have a uniform composition and appearance throughout.
  • Particle Size: The particles of solute in a solution are at the molecular or ionic level, usually smaller than 1 nanometer.
  • Transparency: Many solutions are clear and do not scatter light, although some may be colored.

Types of Solutions

  • Liquid Solutions: Most common; involves liquids (e.g., saltwater, sugar water).
  • Gaseous Solutions: Involves gases (e.g., air is a mixture of gases).
  • Solid Solutions: Involves solids (e.g., alloys like bronze, which is a mixture of copper and tin).

Properties of Solutions

  • Concentration: Refers to the amount of solute present in a given amount of solvent or solution. It can be expressed in various ways, such as molarity or percentage.
  • Saturation: A solution is saturated when it cannot dissolve any more solute at a given temperature and pressure.
  • Solubility: Refers to the maximum amount of solute that can dissolve in a specific amount of solvent at a given temperature.

Factors Affecting Solubility

  • Temperature: Generally, higher temperatures increase solubility for solids in liquids but can decrease it for gases.
  • Pressure: Increased pressure generally increases the solubility of gases in liquids.
  • Nature of Solute and Solvent: “Like dissolves like” principle; polar solvents dissolve polar solutes, while nonpolar solvents dissolve nonpolar solutes.

Applications of Solutions

  • Solutions are essential in various fields, including chemistry, biology, medicine, and industry.
  • Common examples include drinking solutions (e.g., lemonade), cleaning products (e.g., detergents), and pharmaceuticals (e.g., saline solutions).

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