CHEM1102 Electrochemistry Equations
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Oxidation is what?
Reduction is what?
 Oxidation
 Is
 Loss of electrons
 Reduction
 Is
 Gain in electrons

Anode and Cathode
polarity?, ox/red?, flow?
 Anode  is where oxidation occurs (vowels)
  is negative
 Cathode  is where reduction occurs (const.)
  is positive
 Electron flow: Anode > Cathode

Standard Reduction Potential
 ε_{0}
 +ve is better at reduction (cathode)

Standard Cell Potential
E^{0}_{cell} =
E^{0}cell = ε^{0}_{cathode}  ε^{0}_{anode}

Electrochemistry
Gibb's Free Energy
ΔG^{0} =
 ΔG0 = Σv_{B}Δ_{f}G^{0}
 = nFE^{0}_{cell}
 where V_{B} = + for prod and  for react
 where F = 96485 Cmol^{1}

Nernst Equation
E_{cell} =
E^{0}_{cell} =
 E_{cell} = E^{0}_{cell}  (RT/nF) lnQ
 E^{0}_{cell} = (RT/nF) lnK
(cell reaction is unidirectional at +0.3V)

Solubility
For Standard Hydrogen Electrode
ε^{}_{other} =
(find s)
 ε_{other} = ε^{0}_{other}  (RT/nF) ln (1/[solution]^{m})
 (s is [solution] (mol L^{1}), and m is coefficient moles of soluble ion)

Electrolysis
Q =
 Q = ξ nF
 Q = It
 where ξ is extent of reaction in moles
 I is current

Evolution of Oxygen
 reaction
 what is standard reduction potential when it happens?
ε =
 O_{2} + 4H^{+} + 4e^{} = 2H_{2}O
 SRP is +ve
 ε = ε^{0}  (RT/4F) ln (1/(P_{O2}[H^{+}]^{4}))

Evolution of Hydrogen
 reaction
 what is standard reduction potential when it happens?
ε =
 2H^{+} + 2e^{} = H_{2}
 SRP is ve
 ε = ε^{0}  (RT/2F) ln (P_{H2}/[H^{+}]^{2})