Overview
This lecture discusses the principles and common methods of separating mixtures based on physical properties, highlighting their applications in daily life and industry.
Principles of Mixture Separation
- A mixture contains two or more substances combined physically.
- Separation is needed to obtain pure substances from mixtures.
- Separation relies on differences in physical properties like state, particle size, melting point, boiling point, magnetism, and solubility.
Common Methods of Separation
- Filtration is used to separate insoluble solids from liquids by particle size differences.
- Centrifugation separates very fine solid particles from liquids, especially useful for small quantities.
- Distillation separates liquids based on differences in boiling points.
- Chromatography separates and identifies substances in a mixture based on their movement through a medium.
- Sublimation separates mixtures where one solid can convert directly to gas, leaving others behind.
Everyday and Industrial Applications
- Filtration is commonly used for water purification.
- Distillation is used in daily life and industry to refine and separate liquids (e.g., alcohol, petroleum).
- Centrifugation is used in medical labs to separate blood components.
- Chromatography is used for urine drug tests and to analyze dyes.
Key Terms & Definitions
- Mixture — a physical combination of two or more substances.
- Filtration — separation of insoluble solids from liquids using a filter.
- Centrifugation — separation by spinning to sediment fine particles.
- Distillation — separation of liquids by differences in boiling points.
- Chromatography — separation and identification of mixture components based on movement in a medium.
- Sublimation — separation relying on a solid changing directly to gas, leaving non-subliming solids.
Action Items / Next Steps
- Review each separation method and note which physical property it exploits.
- Prepare examples of each method for class discussion.
- Complete assigned reading on real-world applications of mixture separation.