Types of Mixtures

Mixtures

• They are substances held together by physical forces, not chemical and are not chemically combined.

•This mean a mixture will keep it’s own identity.

• Can be separated by simple physical methods.

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Heterogeneous• The substances are not uniformly mixed.• Different substances can be seen.

• Example: Sand in a glass of water, cookie dough, lucky charms.

Homogeneous• Uniformly distributed (are evenly mixed)

•Particles are very small -- it is difficult to see each substance in the mixture.

• Examples: sugar and water, milk, air.

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• Solutions – Well mixed mixtures that have the same properties throughout. (particles can’t bee seen and don’t settle over time)

Examples:

• Colloids – well mixed mixture that has undissolved particles that will not settle over time.

Examples:

Types of Homogeneous Mixtures

Separating Mixtures

Physically picking apart a Mixture by hand

Picking apart different substances from a mixture and placing them in different containers or piles

Sieving

• Using screens of different sizes to separate a mixture into its different sized components.

Magnets

• Magnetic attraction can be used to separate the metals Iron (Fe), Nickel (Ni), and Cobalt (Co) from a mixture.

Filtration

• Using filters to separate solid materials from liquids

Decanting

• Pouring off liquids for solids

Evaporation or Boiling

• Evaporation or boiling off a liquid separates liquids for dissolved solids

Distillation

• Separation of 2 liquids with different boiling point temperatures

Centrifuge• Separates substances of different densities• Solids from liquids• Different density liquids• Blood platelets from blood plasma