Mixture Separation Methods Quiz

Mixture Separation Methods

• Pure substances in mixtures can be separated physically because no new compounds are formed.
• Separation methods depend on the physical properties of mixture components and the desired component.

Paper Chromatography

• Principle: Solubility differences between the solvent and the pigments.
• Use: Separating and identifying pigments in inks and dyes.
• Process: Solvent travels up paper; pigments dissolve. Pigments travel at different speeds based on their solubility in the paper and solvent.
• Solubility Indicator: Distance travelled indicates pigment solubility in the mediums.

Filtration

• Principle: Particle size differences.
• Use: Separating a solid from a liquid in a suspension.
• Process: Liquid passes through holes in a filter while solid (insoluble material) is retained.

Decanting

• Principle: Density differences.
• Use: Separating liquids of different densities or immiscible liquids.
• Process: The denser component settles; the less dense liquid (the solvent) is poured off.
• Equipment: Separating funnel.

Crystallization

• Principle: Differences in boiling points.
• Use: Separating a soluble solid from its solution.
• This method ensures that the solid is separated and the solvent is recovered.

Distillation

• Principle: Differences in boiling points.
• Use: Separating components in mixtures, recovering solvents, separating multiple liquids.
• Types: Simple and Fractional.

Simple Distillation

• Use: Separating solvents or separating solvent and dissolved solids.
• Process: Mixture heated to solvent's boiling point; solvent vaporizes. Vapor rises, flows through condenser as cold water cools the vapor—creating a liquid distillate. This repeats until all the solvent is collected

Fractional Distillation

• Use: Separating multiple miscible liquids with closely-spaced boiling points.
• Process: Utilizes a fractionating column, which allows for multiple vaporization and condensation cycles within the column.
• Result: Over time, the more volatile (lower boiling point) liquid dominates the vapors at the top of the column. This pure vapor is condensed and collected, the temperature monitored, and the process repeated for consecutive liquids.