Unit 12 Chemistry, Liquids, Solids, Intermolecular Forces

• Intermolecular forces - attractive forces that exist between molecules
• Gases-

  • Low densities
  • Indefinite Shape
  • Indefinite volume
  • Weak IMF
• Liquids-

  • Medium densities
  • Indefinite Shape
  • Definite volume
  • Moderate IMF
• Solids-

  • High densities
  • Definite Shape
  • Definite volume
  • Strong IMF
  • Crystalline (ordered) or amorphous (disordered)
• Viscosity - resistance of a liquid to flow
• Greater viscosity = greater IMF
• Rate of vaporization increases with -

  • Increasing surface area
  • Increasing Temperature
  • Decreasing IMF
• Volatile - liquids that evaporate easily
• Condensation and Evaporation are opposites
• Dynamic equilibrium - Rate of condensation and evaporation are equal
• Vapor pressure increases with -

  • Increasing Temperature
  • Decreasing IMF
• Mixture of Boiling water and steam = ALWAYS temp of 100*c (at 1atm)
• Evaporation = Endothermic (heat absorbed)
• Condensation = Exothermic (heat released)
• Heat to vaporize 1 mol of liquid is (ΔHvap)

  ΔHvap of water is 40.7 kJ/mol
• Heat to melt 1 mol of liquid is (ΔHfus)

  ΔHfus of water is 6.02 kJ/mol
• Miscible - Polar-Polar, Nonpolar-Nonpolar
• H bond - F, O, N