EXTENDED COLLIGATIVE

• Colligative properties


  Intensive properties that do not change when you add no extra moles of the substance
• Colligative properties include boiling point, freezing point, vapor pressure, and osmotic pressure
• Intensive properties do not change even if you add certain amounts of moles or mass
• When you add a solute to a solvent

  The colligative properties change
• Nonelectrolyte solutes


  Cosolutes, usually polar substances like sugar
• Electrolyte solutes


  Ionic in nature, like salts
• Electrolyte solutes


  Have a greater effect on colligative properties than nonelectrolyte solutes
• Vapor pressure


  1. Molecules escape into gaseous state

  2. Vapor collides with container walls

  3. Vapor pressure builds up
• In a closed container

  Vapor molecules can return to liquid state through condensation
• Volatile substances


  Readily evaporate, like alcohol and acetone
• Nonvolatile substances


  Have low vapor pressure and low escaping tendency, like water
• When a nonvolatile solute is dissolved in water


  The solute molecules take up space at the surface, preventing the escape of solvent molecules
• The greater the concentration of solute


  The greater the vapor pressure reduction
• Solutions with electrolyte solutes

  Have lower vapor pressure than solutions with nonelectrolyte solutes
• Boiling point


  The temperature at which the vapor pressure of a liquid equals the atmospheric pressure
• Liquids with high vapor pressure boil at lower temperatures
• Boiling point


  The temperature threshold of a liquid before it vaporizes
• Vapor pressure


  The pressure exerted by the vapor of a liquid in equilibrium with the liquid surface
• If a liquid has a high vapor pressure

  The molecules evaporate faster and it takes a shorter time to equalize the vapor pressure of the liquid and atmospheric pressure
• Boiling point


  The point at which the vapor pressure of the liquid equals the pressure surrounding the liquid, and bubbles of vapor form inside the liquid
• Boiling point


  Occurs when vapor pressure equals atmospheric pressure
• Bagio City vs Cotabato City

  • Bagio City is elevated on a plateau, Cotabato City is located in the Mindanao River Basin and prone to flooding as it is below sea level
• Atmospheric pressure


  Equal to vapor pressure at boiling point
• Solute


  A substance dissolved in a solvent to form a solution
• Boiling point of a solution

  Higher than the boiling point of the pure solvent
• Freezing point


  The temperature at which the solid and liquid phase of a substance coexist
• Adding a non-volatile solute to a solvent

  Lowers the freezing point of the solvent
• Electrolytes


  Compounds that ionize in solution, producing a greater number of particles that depress the freezing point more than non-electrolytes
• Osmotic pressure


  The pressure required to prevent the flow of solvent through a semi-permeable membrane from a region of lower solute concentration to a region of higher solute concentration
• Osmotic pressure


  Increases with the number or concentration of solute particles
• Osmotic pressure


  Prevents the flow of water, making it difficult for water to flow into a solution with high solute concentration
• Colligative properties


  Properties of solutions that depend on the concentration of solute particles but not their identity
• Colligative properties


  • Boiling point elevation
  • Freezing point depression
  • Vapor pressure lowering
  • Osmotic pressure
• Colligative properties that increase with solute concentration are boiling point elevation and osmotic pressure
• Colligative properties that decrease with solute concentration are freezing point depression and vapor pressure lowering