Mixtures

Mixtures

1. Homogenous Mixtures

   • Solutions
     • A homogenous mixture throughout two or more substances are evenly dispersed
     • Made of the solute and solvent
       • Solute: the substance that dissolves in the solvent
         • Usually a solid
         • Present in a smaller amount
       • Solvent: the substance in which the solute dissolves
         • Usually water
           • Water is the universal solvent
             • Water can dissolve ionic compounds
               • Water is a polar compound
                 • Polar: Describes a molecule in which the positive and negative charges are separated
               • Water molecules can attract both positive ions and negative ions
               • Polar molecules pul ionic crystals apart
                 • The partially negative oxygen atoms of water molecules attract the positively charged ions
                 • The partially positive hydrogen atoms of water molecules attract the negatively charged ions
     • Miscible liquids mix to form solutions
       • Distillation: a method used to separate miscible liquids that have different boiling points
       • Sometimes, liquid solutions do not contain water
     • Alloy: solid or liquid mixture of two or more metals

2. Heterongenous Mixtures

   • Suspensions
     • A mixture in which particles of a material are more or less evenly dispersed throughout a liquid or gas
     • Particles in a suspension are large
       • Particles can settle out over time
       • Particles can be filtered out
     • Immiscible liquids can separate and form suspensions
       • Example: oil and vinegar
       • Decanting: a process of pouring a less dense liquid off a denser liquid
   • Colloid
     • A mixtue consiting of tiny particles that are intermediate in size between those in solutions and those in suspensions that are in a liquid, solid, or gas
     • Particles in a colloid are small
       • Too small to settle out
       • Large enough to settle out
     • Examples
       • Gelatin desserts
       • Egg whites
       • Blood plasma
     • Some immiscible liquids can form colloids
       • Emulsion: any mixture of two or more immiscible liquids in which one liquid is dispersed in the other
         • Stabilzed with an emulsifier