A Matter of Fact

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A Matter of Fact

• Solutions, Suspensions and Colloids

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What is a Mixture?

• Mixtures two or more substances that are not
  chemically combined with each other and can be
  separated by physical means. The substances in a
  mixture retain their individual properties.
• Two types
• Heterogeneous Mixtures (cereal, salad)
• Homogeneous Mixture (paint)

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Two types of Mixtures
Mixtures
Homogeneous Mixtures
Heterogeneous Mixtures
Solutions
Colloids
Alloys
Suspensions
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Solutions

• A type of homogeneous mixture formed when one
  substance dissolves in another.
• It is the best mixed of all mixtures.
• Same appearance and properties throughout

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Solvent and Solute

• A solution always has a substance that is
  dissolved and a substance that does the
  dissolving.
• Solute -substance that is dissolved
• Solvent -substance that does the dissolving

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Animation of NaCl dissolving in H2O

• Dissolving a Salt.swf

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Solutes

• Insoluble Unable to dissolve in the solvent
• Soluble Able to dissolve in the solvent

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The Universal Solvent Water
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Water as a Solvent

• Many liquid solutions contain water as the
  solvent.
• Ocean water is basically a water solution that
  contains many salts.
• Body fluids are also
• water solutions.

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Concentration of a Solution

• Concentration is a measure of how much solute is
  dissolved in the solvent.
• Concentrated Orange Juice
• Concentrated Laundry Detergent
• Opposite of concentrated is dilute.

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Solubility

• The amount of solute that can dissolve in a given
  amount of solvent.
• Example What happens if you add a lot of sugar
  to a glass of iced tea?
• Solubility of solids in liquids increases with
  temperature.
• You can add more sugar to hot tea than iced tea.
• Solubility of gases in liquids decreases with
  temperature.
• You can keep more bubbles in cold soda than warm
  soda.

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Speed up Dissolving?

• Mixing
• Heating
• Crushing

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Solutions are made from solutes and solvents from
all states of matter.Example Air is a
solution of oxygen and other gases (solutes)
dissolved in nitrogen (solvent).
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Types of solutions

• Solute Solvent Example
• Gas Gas
• Air (oxygen in nitrogen)
• Gas Liquid
• Soda water
• (CO2 in H2O)
• Solid Liquid
• Ocean water
• (salt in water)
• Solid Solid
• Gold jewelry (copper in gold), brass,
  bronze, pewter, solder

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Types of Solutions

• Solute               Solvent         Example
• Liquid               Gas                Humid Air
• Liquid               Liquid           
  Antifreeze  
• ethylene glycol in H2O
• Liquid               Solid              Dental
  fillings  
• Hg in Ag
• Solid                 Gas                Soot,
  dust in air

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Alloys

• Metals dissolved in metals are called alloys.

Stainless steel is a mixture of iron and
chromium.
Brass is an alloy of copper and zinc.
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Suspensions

• Suspensions are mixtures containing large
  particles.
• If you shake or stir a suspension, the particles
  will disperse, but will eventually settle out or
  separate.
• Particles of a suspension will scatter light.

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Colloids

• Colloids are mixtures containing relatively large
  particles that do not settle out.
• The particles are dispersed throughout the
  mixture, but are not dissolved.
• Particles of a colloid will scatter light.

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Types of Colloids

• Gas               Liquid            FOAMS,
  whipped cream, mousse
• Liquid            Gas                FOG, Clouds
• Liquid            Liquid            EMULSIONS
  Mayonnaise,oil,vinegar,egg yolk
• Liquid            Solid              butter and
  other gels
• Solid              Gas               SMOKES, all
  kinds
• Solid              Liquid           SOLS, Paint
  pigment -many are metallic - in H2O or oil
• Gas Solid Marshmallows
•  

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Separation Techniques

• Magnets based on magnetism of the matter
• Centrifugation based on densities of the matter
• Ex blood is broken down into red blood cells,
  platelets, plasma

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Chromotography

• Means Color Writing
• It involves passing a mixture dissolved in a
  mobile phase through a stationary phase.
• Components travel at different speeds based on
  their size and therefore separate along the way.

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Separation Techniques

• The Distillation Process
• Distillation is a process used to separate a
  mixture into components based on boiling points
• Involves a change of state, usually from liquid
  to gas, and then condensation to return the now
  separated component to liquid state.
• The distillation apparatus (still) has three
  parts (1) A flask with an outlet tube,(2) A
  condenser, and(3) A vessel.

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Distillation