CHEM 102 1nd Edition Lecture 35Outline of Last Lecture I. ElectrolysisII. OvervoltageIII. RelationshipOutline of Current Lecture I. RelationshipII. SpontaneityIII. Find G, K, EIV. At Non-Standard ConditionsCurrent LectureI. Relationships- The constants can be combined E° = RT/nF ln K = 0.0257/n ln K- Another alternative is using log E° = 2.303 (0.0257/n) log K= 0.0592/n logK- K and G° G = -RTlnK- G° and E° G = -nFE°- K and E° E° = (0.0592/n)logK E° = (0.0257/n)lnK- G° G = H -TSII. Spontaneity - Spontaneous ΔG° = negative K > 1 E° = positive- Non-Spontaneous ΔG° = positiveThese notes represent a detailed interpretation of the professor’s lecture. GradeBuddy is best used as a supplement to your own notes, not as a substitute. K <1 E° = negative- At Equilibrium ΔG° = 0 K = 1 E° = 0III. Find G, K, E° - Consider:- 2Br- + Cl2 Br2 + 2Cl- First, find E° 2Br- Br2 + 2e-; E = -1.07V 2e- + Cl2 2Cl-; E = 1.36V E° of cell is 0.29 V- Find G using G = -nFE° G° = -(2mol e-)(96,500 J/molV)(.29V) =-56 kJ- Find K E = 0.0592/n logK 0.29V = 0.0592/2mole- (logK) 9.80 = logK 6.3e9 = KIV. At Non-Standard Conditions- E = E° - 0.0592/n logQ- At equilibrium E = 0 Q=K 0 = E° - 0.0592/n logK- Find the E for Non-Standard Cell Given: Cu|Cu2+ (1.0M)||Ag+(0.50M)|Ag E=E° - 0.0592/n logQ To Find E° Cu Cu2+ + 2e-; E° = -0.34V 2e- + 2Ag2+ 2Ag; E°=0.80V E° of cell = 0.46V Overall Equation: Cu + 2Ag+ Cu2+ + 2Ag E = E° - 0.0592/n logQ E = 0.46 – 0.0592/n log [Cu2+]/[Ag+]2 E = 0.46 – 0.0592/n log [1]/[0.50]2 E =
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