Post on 21-Jan-2016
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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.
Images are from http://www.chem4kids.com
• 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