Mixtures: Types and Separation Methods

Mixtures

• Mixtures are matter with variable composition.
• Mixtures are demonstrably different from elements and compounds.
• Mixtures can be heterogeneous or homogeneous.

Objectives

• Recognize mixtures.
• Identify types of mixtures.
• Learn methods of separating mixtures.

What is a Mixture?

• A mixture is composed of two or more different substances that are not chemically combined.
• Mixtures demonstrate physical, not chemical changes.
• Examples include fruit salad, candy mix, and sand in water.

Types of Mixtures

• Heterogeneous Mixture: Substances are not evenly distributed.

  • Components are noticeably different.
  • Examples: sand and water, salad, oil and water.

• Homogeneous Mixture: Substances are uniformly distributed.

  • Components are not visible.
  • Examples: saltwater, tea, air.

Separating Mixtures

• Mechanical Separation: Separating mixtures through physical means (color, shape, etc.).

  • Picking out colorful candies, separating iron filings with a magnet.

• Filtration: Used to separate solids from liquids.

  • Sand and water are separated using a filter paper.

• Evaporation: Separating a solid dissolved in a liquid.

  • Saltwater is heated, the water evaporates, leaving the salt behind.

• Separating Funnel: Used to separate immiscible liquids.

  • Oil and water mixtures are separated using a separating funnel.

• Distillation: Separating liquids in a mixture based on boiling points.

  • Different liquids in a mixture are separated based on differing boiling points.

Homework

• Create a mixture and develop a method to separate.
• Document the process with visuals (pictures or video).

Activity Examples

• Separating Iron Filings, Salt, and Sand: Magnet to remove iron, add water to dissolve salt, use filtration to separate salt from sand.

• Separating Palm Oil and Water: Utilize a separating funnel to separate the immiscible liquids.

Compound vs. Mixture

• Compounds are chemically bonded, whereas mixtures are not.
• Compounds have fixed proportions of elements.
• Mixtures can be separated via physical methods.

Additional Questions

• Which mixtures are compounds?
• Which categories can be separated easily?
• Is salad a compound?