Dissolution

• What are the three types of osmotic solutions?

  Hypotonic, hypertonic, isotonic
• What happens to cells in a hypertonic solution?

  Cells become plasmolysed
• What occurs to cells in a hypotonic medium?

  Cells swell and may burst
• How do moulds and yeasts compare to bacteria regarding osmotic pressure?

  Moulds and yeasts are more tolerant of high osmotic pressure than bacteria
• What is the relationship between ΔTb and Δp according to the study material?

  The ratio between ΔTb and Δp is constant
• What does Raoult's law state about ΔTb?

  ΔTb = k X2
• What is the formula for calculating ΔTb in diluted aqueous solutions?

  ΔTb = kb m
• What is the role of a semi-permeable membrane in osmosis?

  It allows solvent molecules to pass but not solute molecules
• What is osmotic pressure?

  It is the pressure needed to stop osmosis
• What is the equation for osmotic pressure for non-electrolytes?

  pV = nRT
• How does the osmotic pressure of a 1.0 M NaCl solution compare to a 1.0 M CH3OH solution?

  The NaCl solution has twice the osmotic pressure of the CH3OH solution
• What must be used for real solutions instead of concentration?

  Activity must be used instead of concentration
• What does the vapour pressure curve for a solution indicate?

  It lies below that of the pure solvent

  
• What happens to the boiling point of a solution compared to the pure solvent?

  A solution will boil at a higher temperature than the pure solvent

  
• How do you calculate the moles of sucrose in a solution?

  n2 = w2 / M2
• How do you calculate the relative vapour pressure lowering?

  Δp / p1o = n2 / (n1 + n2)

  
• What effect do solute molecules have on the volatility of a solvent?

  Solute molecules decrease the volatility of the solvent
• What are the colligative properties of solutions?

  • Vapor pressure lowering
  • Boiling point elevation
  • Freezing point depression
  • Osmotic pressure
• What is the definition of an ideal solution?

  An ideal solution has no change in properties other than dilution when mixed
• What is the significance of adhesion and cohesion in real solutions?

  Adhesion and cohesion determine the deviation from ideality in solutions
• What is the role of CFCs in propellants?

  CFCs are perfectly miscible with each other
• How do you calculate the partial vapour pressure of a component in a solution?

  Psolute = ksolute Xsolute
• What does Raoult's Law state about the partial vapour pressure of a volatile constituent?

  It is equal to the vapour pressure of the pure constituent multiplied by its mole fraction

  
• What happens to the escaping tendency of water molecules when pressure is applied?

  The escaping tendency decreases with increased pressure
• What is the relationship between temperature and escaping tendency?

  Higher temperature increases the escaping tendency