Chem 1a Section 2

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Chem 1a Section 2

• Final Exam Topics

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• Final Exam Test Topics
  Chemical Thermodynamics
• Let the lectures, handouts,
  and homework be your guide
• I. First Law
• Definitions of system, surroundings, etc. sign
  convention
• Heat (q), Heat Capacity, Calorimetry, qv, qp, H
  ? E PV, State Functions
• Hesss Law standard states, ?Hof, ?Hocomb,
  ?Hor, endo vs. exothermic
• Work (w) , sign convention, Force thru distance,
  PV work
• Energy, Eint, ?E q w, state function, energy
  is conserved
• II. Second Law
• Spontaneous Process, Development of Entropy
  probability, microstates, example of expansion
• of ideal gas, SklnW, ?S?qrev/T, equivalence of
  these two expressions,
• Third Law Absolute S tabulated

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• III. Gibbs Free Keq
• ?G with change in conditions ?Grxn,T
  ?G?r,T RTlnQ ?G?r,T - RT ln Keq or Keq
  e-?Gor,T ,
• Keq ? f(P) ?G f(T), but ?H, ?S ? f(T)
  so use ?G? ?H?-T?S? lnKeq(T) ?H?/RT - ?S?/RT
• 
  or lnKeq(T2)
  - lnKeq(T1) -?H?/R(1/T2 - 1/T1)
• IV. Electrochemistry, Thermodynamics, Keq
• Balancing Redox via ½ reactions
  Concentration Cell
• Galvanic Cell anode (oxidation), cathode
  (reduction), salt bridge or porous plug
  wire/ammeter
• current I (amps) charge Q (coulombs)
  Faraday constant
• ?E cell voltage (measured with
  potentiometer)
• electrolytic cell (driving rxn in reverse
  of spontaneous direction) cell representations
• ?G wother wext welec for rev.
  process Cell to measure ?G -Q?E -nF?E
  (rev.) ?G? -nF?E?