Separation of Mixtures

Separation of Mixtures

• Mixtures, both homogeneous and heterogeneous, can be separated by physical changes.

Techniques used for separating mixtures

• Separation by physical properties• Filtration• Distillation• Crystallization• Evaporation to dryness• Chromatography

Separation by properties

• Physical characteristics such as color, size, density, magnetism, etc can be used to separate mixtures.

• Example: separating iron from a mixture. separating a layer of oil from water separating red marbles from blue

marbles

Separation by filtrationHeterogeneous mixtures composed of insoluble solids in liquids are easily separated by filtration.Equipment used during this process includes a funnel and filter paper.The liquid which passes through the filter paper is called the filtrate.Example: sand in water

Evaporation to dryness.

• Homogeneous mixtures composed of dissolved solids in a solvent can be separated by boiling off the liquid. The solute remains in the evaporating dish.

• Equipment required involves a hot plate and evaporating dish.

• Example: salt dissolved in water

Distillation

• Distillation is used to separate a solution of two liquids. It is based on differences in the boiling points of the two substances involved.

• When the solution is heated, the substance with the lowest boiling point boils and changes to a vapor. The vapor condenses as it passes through the condenser and is collected.

• Example: separating water from the syrup in a coke.separating alcohol from water

Distillation

Crystallization

• A solution containing a dissolved solute can also be separated using crystallization.

• When the solution contains as much of the dissolved substance as possible, the addition of even a tiny amount can cause the dissolved substance to come out of solution and collect on any available surface.

• Example: the making of rock candy from a sugar solution.

Crystallization

Chromatography

• Chromatography is a technique that separates two liquid components of mixture from each other based on the ability of each substance to travel up the surface of another material (called the stationary phase).

• The stationary phase is often a solid such as the chromatography paper.

• Components with the strongest attraction for the paper travel slower.

• Example: separating dyes in food coloring

Chromatography

How would a mixture of two colorless liquids be separated?

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1. Chromatography2. Distillation3. Evaporation to Dryness4. Filtration

What is the most efficient way of separating a non-dissolving solid from a

liquid?

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25% 1. Chromatography2. Distillation3. Evaporation to Dryness4. Filtration

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What technique should be used to separate a mixture of red and blue marbles of the same

size and mass?

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1. Chromatography2. Distillation3. Filtration4. Separation by Properties

How can you separate the components of paint?

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1. Chromatography2. Distillation3. Evaporation to Dryness4. Filtration

How can you separate vinegar and oil?

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1. Chromatography2. Evaporation to Dryness3. Filtration4. Separation by Properties

How would you separate vinegar from water?

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1. Chromatography2. Distillation3. Evaporation to Dryness4. Filtration

Distillation results in the formation of solid particles of a dissolved substance?

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1. True2. False

Filtration depends on differences in sizes of particles.

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1. True2. False

Separations of mixtures depend on the chemical properties of the substances

involved.

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1. True2. False

Chromatography depends on the different boiling points.

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1. True2. False

Evaporation to dryness can be used to separate two liquids.

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1. True2. False