Mixtures and Solutions

Flashcards on Mixtures and Solutions

Basic Concepts of Matter

  • Matter: Anything that has mass and takes up space.

  • Pure Substance: Matter with both definite and constant composition and distinct chemical properties.

Classification of Substances

  • Element: A substance that cannot be broken into simpler substances by chemical means.

  • Compound: A substance made up of atoms of different elements.

  • Mixture: Material made up of 2 or more substances that can be separated by physical means.

Types of Mixtures

  • Heterogeneous Mixture: A mixture where different substances can easily be seen due to uneven mixing.

    • Examples: Orange juice, fruit salad.

  • Homogeneous Mixture: A mixture in which the substances are evenly mixed throughout.

    • Solution: A homogeneous mixture where different substances cannot be seen, even with a microscope.

    • Examples: Salt water, Kool-aid.

Specific Mixture Characteristics

  • Immiscible: Liquids that do not mix (e.g., oil and vinegar salad dressing).

  • Miscible: Two or more liquids that will mix (e.g., rubbing alcohol, gasoline).

  • Colloid: A mixture that does not settle; particles are unevenly mixed and scatter light via the Tyndall effect.

    • Tyndall Effect: The scattering of a beam of light as it shines through a colloid.

  • Suspension: Contains a liquid and particles that visibly separate out over time.

    • Examples: Italian salad dressing, orange juice with pulp.

Components of Solutions

  • Solute: The substance being dissolved (e.g., salt, Kool-aid powder).

  • Solvent: The substance doing the dissolving (e.g., water).

  • Alloy: A mixture of two or more metals (e.g., penny, brass).

Factors Affecting the Rate of Dissolving

  • The rate of dissolving increases with:

    • Agitation (stirring).

    • Higher temperature.

    • Increased surface area.

Separation Techniques

  • Filtration: Separating substances based on size.

  • Distillation: Separating substances based on boiling point.

  • Chromatography: Separating substances by their movement through another substance.

  • Crystallization: Evaporating a liquid to leave behind dissolved solids.

Solubility Concepts

  • Solubility: The maximum amount of solute that will dissolve in a specific amount of solvent at a certain temperature.

  • Saturated Solution: A solution that has dissolved all the solute possible.

  • Unsaturated Solution: A solution that can still dissolve more solute.

  • Supersaturated Solution: A solution that has dissolved more solute than possible at a given temperature.

  • Concentrated vs. Dilute:

    • A concentrated solution has a large amount of solute dissolved.

    • A dilute solution has a small amount of solute dissolved.

Colligative Properties

  • Freezing Point Depression: The presence of particles interferes with the organization of a solid, necessitating even colder temperatures for freezing.

    • Examples: Road salt, antifreeze.

  • Boiling Point Elevation: The presence of particles interferes with evaporation, requiring the solution to reach a higher temperature to boil.

    • Example: Salt water.