Chapters 7 and 9

  1. Solution
    a homogenous mixture of two of more compounds

    ex. sugar in water, oxygen in watere, air, dental fillings, saline
  2. In a solution:
    • the solute can't be filtered out
    • always stays mixed
    • particles are always in motion
    • volumes are not additive
    • may have different properties
  3. solvent
    component in the greater extent
  4. solute
    component in the lesser extent ( you may have more than one)
  5. Physical states of solutions
    • exist in any of the three states
    • solids:dental fillings 14K gold, sterling silver
    • liquid:saline, vodka, vinegar, sugar water
    • gas:the atomsphere, anesthesia gases
  6. solubility
    a measure of how much a solute can be dissolved in a solvent
  7. common unit for solubility
  8. factors that affect solubility
    • temperature
    • pressure
    • polarity
  9. saturation
    when a solution contains as much solute as it can at a given temperature
  10. unsaturated
    can still dissolve more
  11. saturated
    have dissolved all you can (max. amount)
  12. supersaturated
    temporarily has dissolved more than normally would be dissolved at the certain temp.
  13. effect of temperature for gases and most liquids
    solubility decreases when solution temp. increases
  14. effect of temperature for solids
    solubility increases when solution temp. increases
  15. effect of pressure on states of matter
    • little effect of solid and liquids
    • will greatly increase solubility of gases
  16. weight/volume %
    mass solution(g)/ total volume(mL) X 100
  17. volume/ volume %
    volume solute (mL)/ total volume (mL) X 100

    the solution consists of 2 parts, the solute + the solvent. watch how the problem is worded
  18. weight/ weight %
    mass solute (g)/ total mass (g) X 100
  19. molarity formula
    moles solute/ liters of solution (1)
  20. molarity
    • recognizes that compounds have different formula weights
    • A 1 M solution contains the same number of molecules as 1 M of ethanol
    • []- special symbol which means molar (mol/l)
  21. Hints for solving problems
    if given the concentration
    • moles/ liters
    • allows 1 liter unless told otherwise
  22. if given both the mass & volume
  23. if you are asked to solve for the volume invert the concentration factor
    liter/ moles
  24. dilution
    once you have a solution; it canbe diluted by adding more solvent. this is also important for materials only available as solutions
  25. formula of dilution
    • M1V1=M2V2
    • C1V1=C2V2
    • Any volume or concentration unit can be used as long as you use the same units on both sides of the equation
  26. Solution Stoichiometry
    • extension of earlier stoichiometry problems
    • first step is to determine the number of moles bases on solution concentration and volume
    • final step is to convert back to volume or concentration as required by the problem
    • you still need a balanced equation and must use the coefficiant for working the problem
  27. properties of electrolytic
    • ionic compounds in polar solutions
    • dissociate in solution to make ions
    • conduct electricity
    • may be strong (100% dissociation) or weak (less than 100%)
  28. Properties of nonelectrolytic
    • do not conduct electricity
    • solute is dispersed but does not dissolve
  29. dissolving ionic compounds
    when an ionic solid dissolves in water the polar solvent removes ions from the crystal lattic
  30. dissolving covalent compounds
    covalent compounds do not dissociate
  31. ions in solutions
    • when ionic materials dissolve in water
    • they dissociate: we show them as ions
  32. osmotic pressure
    the pressure required to stop osmosis. the amount of external pressure applied to the more concentrated solution to stop the passage of solvent molecules across a semipermeable membrane
  33. osmotic pressure formula
    osmotic pressre=nMRT
  34. colligative properties
    • "bulk" properties that change when you add a solute to make a solution
    • based on how much you add
    • effect of ionic materials is based on number of ions produced
    • vapor pressure lowering
    • freezing point depression
    • boiling point elevation
    • osmotic pressure
  35. vapor pressure
    all colligative properties are based on Raoult's Law
  36. Raoult's Law
    when a solute is added to a solvent, the presssure of the solution is due to the parital pressure of the solvent
  37. freezing point depression
    • when you add a solute to a solvent, the melting point goes down
    • the more you add, the lower it gets
    • this will only work until you reach saturation
    • FP depression=(number of particles)(freezing point)(molerity)
  38. boiling point elevation
    • when you add a solution to a solvant, the boiling point will go up
    • the more you add, the hight it goes
    • it will only work until you resach saturation
    • BP elevation= (number of particles)(freezing point)(molerity)
Card Set
Chapters 7 and 9
Chapters 7 and 9: Solutions and Acids & Bases