How Solutions Form

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How Solutions Form
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SC Standards Covered

• Standard PS-3.5
• Explain the effects of temperature, particle
  size, and agitation on the rate at which a solid
  dissolves in a liquid.

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What is Solubility?

• A substance is soluble in a substance if it will
  dissolve in that substance.
• Solubility The maximum amount of a substance
  that can dissolve in a given volume at a
  particular temperature and pressure.

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What is a Solution?

• Solution a mixture that has the same
  composition, color, density, and taste throughout
  (homogeneous mixture)

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Two Parts of a Solution

• Solute - substance that is dissolved
• solvent - dissolving medium substance doing
  the dissolving

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Examples of Solutions

• Gas in gas air (oxygen in nitrogen)
• Gas in liquid Soda (carbon dioxide in water)
• Liquid in liquid rubbing alcohol (water in
  alcohol)
• Solid in liquid seawater (salt in water)
• Solid in solid sterling silver (copper in
  silver)

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Alloys

• Alloy - solution of metals dissolved in other
  metals
• Bronze
• Brass
• Sterling silver
• 10K, 14K, 18K Gold
• Stainless steel

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Water the Universal Solvent
d-
Water is polar it has oppositely charged ends
d
Ionic Compounds () and (-) ions
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end of water attaches to (-) ions of crystal
- end of water attaches to () ions of crystal
Ions pulled away from crystal
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Ions surrounded by water molecules
Continues to happen until all ions separated
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Rates of Dissolving

• What are some ways to make things dissolve faster?

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Factors that Increase the Rate of Dissolving
1.) Stirring the Solution - solvent particles
collide with the surface of the solute more
frequently and the dissolving process occurs
faster.
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2.) Heating the Solvent - speeds up the
solvent particles so there are more frequent
collisions between solvent and solute
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• 3.) Smaller Solute Particle Size
• - increases surface area so there are more
  places the solvent can get to the solute and
  pull the particles into solution faster

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What does it mean to be Saturated?

• Saturated Solution
• The maximum mass of solute is dissolved in the
  solvent at a particular temperature
• Saturation is used in crystal formation such as
  in making rock candy and in the forming of
  stalactites and stalagmites in caves.