review deck

• strong acids:

  • HCl
  • HI
  • HBr
  • HNO3
  • H2SO4
  • HClO3
  • HClO4
• strong bases:

  • LiOH
  • BrOH
  • NaOH
  • KOH
  • RbOH
  • CsOH
  • Sr(OH)2
  • Ba(OH)2
• H+:

  • strong acid
  • complete dissociation
  • K = infinity
  • equation: [H+]=Ca
  • pH: 0-2
• OH-:

  • strong base
  • complete dissociation
  • K = infinity
  • equation: [OH-]=Cb
  • pH: 12-14
• HA/BH+:

  • weak acid
  • partial dissociation
  • K = 10^-2 - 10^-10
  • equation: [H+]=(KaCa)^1/2
  • pH: 3-6
• B/A-:

  • weak base
  • partial dissociation
  • K = 10^-2 - 10^-10
  • equation: [OH-]=(KbCb)^1/2
  • pH: 8-11
• theory:

  • arrhenius: "acids + bases are dissociation products of water"
  • 2H2O <--> 2H3O+(hydronium ion) + 2OH- (hydroxide)
  • bronstead: "acid or base makes conjugate form after proton donation"
  • bronstead acid: proton donor that makes conjugate base (HCl donates proton and makes Cl-)
  • bronstead base: proton acceptor that makes conjugate acid (NH3 [B] accepts proton and makes NH4+[BH+])
  • Lewis: "identity based on unbonded electron pair"
  • lewis acid: empty orbits allows electron exception (BH3)
  • lewis base: unpaired electron allows electron donation (NH3)
• Ranking K:

  • large Ka: stronger acid = more dissociation
  • larger Kb: stronger base = more dissociation

  *** large K --> 10^-4 > 10^-10 ***

  
  

  • weaker acid = larger pH
  • Kw=KaKb=10^-14 ---> stronger acid/base makes weaker conjugate base/acid
• autoprotolysis of water:

  • uses van't hoff and temp dependence to prove dissociation of pure water
  • assume H2O at room temp has a constant concentration of 55.2M
  • Kw = [H+] = [OH-] = 10^-14 (assumed at all T and P)
• Temp dependence:

  • dissociation of water = endothermic
  • T and K direct relationship
  • H+ = (Kw)^1/2
  • cooler temp = pH >7
  • hotter temp = pH <7
• neutralization equations:

  • SA v SB: H+ + OH- <--> H2O
  • SA v WB: H+ + B <--> BH+
  • SA V WB-: H+ + A- <--> HA
  • SB v WA: OH- + HA <--> H2O + A-
  • SB v WA+: OH- + BH+ <--> H2O + B
• neutralization facts:

  • buffers: when strong < weak [pH=pKa]
  • equivalence point: when strong = weak [WB <->WA]
  • excess strong: when strong > weak [pH=SA/SB type]
• complex assumptions:

  • small error when large M + pKa between 3-10 (can ignore Kw)
  • standard T and P
  • 2 species: K value apart from each other by 3-4 units for little error