Chapter 4: Solutions

Chapter 4: Solutions

1. Solute: substance that dissolves in solvent

2. Solvent: substance that is dissolved into (by solute)

3. "Like dissolves like" -> nonpolar to nonpolar, polar to polar

4. Saturation

   • Saturated: solution contains maximum amount of dissolved solute
   • Unsaturated: solution contains less solute than maximum
   • Supersaturated: solution contains more than the maximum solute

5. Electrolytes: substance whose aqueous solution conducts an electric current

   • Nonelectrolytes: substance whose aqueous solution does not conduct an electric current
   • Strong: conducts very efficiently - ionic compounds, strong acids/bases
   • Weak: conduct only a small current - slightly ionized (~covalent), weak acids/bases

6. Ionization/Dissociation

   • Ionic compounds dissociate into their ions in solution
   • Some covalent compounds ionize also

7. Solution Concentration

   • Molarity(M) = moles of solute/liter of solution
   • Dilution: MV1 = MV2

8. Precipitation Reactions

   • Double displacement: AB + CD -> AD + CB
   • Forms precipitate (insol s), and insol g, usually water
   • All sodium, potassium, ammonium, and nitrate salts are soluble in water.
   • Net ionic equations

9. Acids and Bases

   • Acid-Base Reactions
     • Net ionic equation: H+(aq) + OH-(aq) = H2O(l)
   • Acid-Base Titrations
     • Equivalence point
     • Titrant: solution of known concentration

10. Oxidation-Reduction (redox)

    • Electrons are transferred (LEO says GER)
      • LEO: Lose electrons = oxidation
      • GER: Gain electrons = reduction
    • Active metals: lose electrons + oxidize easily
    • Active nonmetals: gain electrons + reduce easily

11. Oxidation Numbers

    • sum of OX numbers in anything is equal to its charge
      • Lone elements = 0 (even diatomics)
    • Hydrogen in compounds = +1
    • Oxygen in compounds = -2