At a potential of -1.0 V (versus SCE), carbon tetrachloride in methanol is reduced to chloroform at a Hg cathode: 2CCl4 + 2H+ + 2e + 2Hg (1) ⇒ 2CHCl3 + Hg2 Cl₂ (8) At -1.80 V, the chloroform further reacts to give methane: 2CHCl3 + 8H+ + Be + 6Hg(1)→ 2CH4 + 3Hg2Cl₂ (8) Several 0.850-g samples containing CC14, CHCl3, and inert organic species were dissolved in methanol and electrolyzed at -1.0 V until the current approached zero. A coulometer indicated the charge required to complete the reaction, as given in the second column of the following table. The potential of the cathode was then adjusted to -1.80 V. The additional charge required to complete the reaction at this potential is given in the third column of the table. Calculate the percent CCl4 and CHCI 3 in each mixture.

At a potential of -1.0 V (versus SCE), carbon tetrachloride in methanol is reduced to chloroform at a Hg cathode: 2CCl4 + 2H+ + 2e + 2Hg (1) ⇒ 2CHCl3 + Hg2 Cl₂ (8) At -1.80 V, the chloroform further reacts to give methane: 2CHCl3 + 8H+ + Be + 6Hg(1)→ 2CH4 + 3Hg2Cl₂ (8) Several 0.850-g samples containing CC14, CHCl3, and inert organic species were dissolved in methanol and electrolyzed at -1.0 V until the current approached zero. A coulometer indicated the charge required to complete the reaction, as given in the second column of the following table. The potential of the cathode was then adjusted to -1.80 V. The additional charge required to complete the reaction at this potential is given in the third column of the table. Calculate the percent CCl4 and CHCI 3 in each mixture.

Chemistry

10th Edition

ISBN:9781305957404

Author:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste

Publisher:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste

Chapter1: Chemical Foundations

Section: Chapter Questions

Problem 1RQ: Define and explain the differences between the following terms. a. law and theory b. theory and...

See similar textbooks

Similar questions

How long would it take (in minutes) to reduce 1 mole of each of the following ions using the current indicated? (Ampere (A) = Coulomb/second (C/s), I = C/s, F= 96500 C/mol e-) (C = Charge unit Coulomb, n = electron mole number) Q=I×t=n×F(a) Fe3+ , 2.344 A (b) Cu2+ , 25.260 A
Determine the potential of a platinum electrode (vs. SHE) when placed in a mixture of 0.00385 M TIC1, and 0.0431 M TICI at 25 °C. T1³+ (aq) + 2 e Tl* (aq) Ept Ept 1.2803 Incorrect || Determine the potential of a platinum electrode when placed in a mixture of 0.0173 M potassium permanganate (KMnO4) and 0.0876 M manganese chloride (MnCl₂) at pH 3.72 and 25 °C. E° = 1.25 V 2+ MnO4 (aq) + 5e + 8 H¹ (aq) = Mn²+ (aq) + 4H₂O(1) Incorrect V E° = 1.51 V V
8.) Determine the potential that needs to be set in the system SnO3² + 3 H3O+ + 2 e = HSnO₂ + H₂O at 25°C in a basic solution (pH = 13), so that the concentration ratio of the two tin forms is [SnO32] : [HSnO₂] = 106. The potential for this half-reaction is Eº= -0.374 V. Answer: E =
write the half-reaction and standard potential of the right half-cell electrode for each of the galvanic cells shown below: Pt | H2,2H + // Pb2 + | Pb E = -0,13V Pt | H2,2H + // Fe3 +, Fe2 + E = 0,77V b) The standard potential of the electrode Zn2 + | Zn is -76V. The standard potential for the galvanic cell Zn | Zn2 + // Sn2 + | Sn is 0.62V. Write the half-reactions that occur at each electrode when this galvanic cell produces current. What is the standard electrode potential? of the electrode Sn2 + | Sn?
2.( J Given the standard reduction potentials (E°) for ubiquinone (Q) and NADP+ provided below, consider the following questions. Q+ 2H+ + 2e ---> QH₂ NADP+ + H+ + 2e---> NADPH Eº⁹ = 0.04 V Eº⁹ = -0.32 V (a) ( Calculate the standard AEº for the oxidation of NADPH by Q. From the reactants in your derived redox reaction, indicate the oxidant and reductant. (b): .) Calculate the standard free energy of the redox reaction in part (a) and indicate if the reaction is exergonic or endergonic.
(a) What quantity of charge (in coulombs) is a fully charged 12-V lead–acid storage battery theoretically capable of furnishing if the spongy lead available for reaction at the anodes weighs 10 kg and there is excess PbO2?(b) What is the theoretical maximum amount of work (in joules) that can be obtained from this battery?
A galvanic cell is constructed in which the overall reac- tion is Pb(s) + 2 H;O* (aq) → Pb²+ (aq) + H2 (g) + 2 H20(e) (a) Calculate AE° for this cell. (b) Chloride ions are added until PbCl, precipitates at the anode and [CI-] reaches 0.15 M. The cell potential is then measured to be 0.22 V at pH = 0 and PH, 1.0 atm. Calculate [Pb2+] under these conditions. (c) Calculate the solubility product constant Kp of PbCl2.
An electrochemical cell similar to the cell in Experiment 3 is constructed, but instead of using Cu electrodes and a Cu²+ solution, this cell uses Pb electrodes and a Pb²+ solution. Pb|Pb+²(1 M)||AsO(~ 1 M)|Pb₂ (AsO₂)₂(s) Pb(s) The measured potential, Ecell of this cell is -0.349 V. Calculate Ksp for Pb, (ASO₂)₂. Ksp = 1.479 x10¹2 Incorrect
. Consider a galvanic cell with the anode containing a Zn metal electrode and a 0.10 M Zn(NO3)2solution and the other half-cell containing a Sn metal electrode and a 0.10 M Sn(NO3)2 solution. If themeasured Ecell value is +650 mV and the Zn2+/Zn reduction potential is assumed to be −790 mV, what isthe Sn2+/Sn reduction potential? Show all work.
2H+(aq)+2e- -> H2(g) under standard conditions (pH=0.00, PH2=1 atm) this standard hydrogen electrode (SHE) is defined to have reduction potential od 0.00 V. What is the reduction potential of a hyrdogen electrode that is still at standard pressure, but has a pH = 6.25, relatove to SHE
+2 t- 4) Consider the following redox reactions and their standard cell potentials: (acidic conditions) (basic conditions) S,0, (aq) + Cl2(g) = HCI0(aq) + So,"(aq) (acidic conditions) cell =-1.31 V E°cell = +0.10 V E° cell = +0.37 V E°. C2(g) + Bio*(aq) = Bi(s)+ HCIO(aq) So(aq) + 03(g) = S20 (aq) + 02(g) a) Using the ½ rxn method, balance the three redox reactions under the conditions indicated. b) Write each balanced redox reaction in the spontaneous direction and indicate its corresponding standard cell potential. c) Between these 3 redox reactions there are FOUR oxidizing agents and FOUR reducing agents. (Hint: You may need to consider the balanced equations.) i) Place the FOUR oxidizing agents in order of decreasing oxidizing strength. (From the strongest OA to the weakest OA.) ii) Place the FOUR reducing agents in order of decreasing reducing strength. ( (From the strongest RA to the weakest RA.)
At 25C, you conduct a titration of 20.00 mL of a 0.0400 M AgNO3 solution with a 0.050 M NaI solution within the following cell: Saturated Calomel Electrode | Titration solution | Ag(s) for the cell as writted, what is the voltage after the addition of 10.00 mL of the NaI sooution? The reduction potential for the saturated calomel electrode is E=0.241 V. The standard reduction potential for the reaction: Ag++e- ® Ag(s) E0= 0.79993V. The solubility constant of AgI is Ksp=8.3x10-17 Note: the cell potential could be negative since the condditions are non-standard ones. a)0.169 b)0.354 c)0.235 d)2.360 e)0.441