SOLVED

21) Balance the following redox reaction if it occurs in basic solution. What are the coefficients in front of Cr(OH)4? and ClO? in the balanced reaction? Cr(OH)4?(aq) + ClO?(aq) → CrO42-(aq) + Cl?(aq) A) Cr(OH)4? = 2, ClO? = 3 B) Cr(OH)4? = 1, ClO? = 1 C) Cr(OH)4? = 1, ClO? = 2 D) Cr(OH)4? = 2, ClO? = 6 E) Cr(OH)4? = 6, ClO? = 5 22) Identify the location of oxidation in an electrochemical cell. A) the anode B) the cathode C) the electrode D) the salt bridge E) the socket 23) Identify the location of reduction in an electrochemical cell. A) the anode B) the cathode C) the electrode D) the salt bridge E) the socket 24) Define a salt bridge. A) A pathway, composed of salt water, that ions pass through. B) A pathway in which no ions flow. C) A pathway between the cathode and anode in which ions are reduced. D) A pathway between the cathode and anode in which ions are oxidized. E) A pathway by which counter ions can flow between the half-cells without the solutions in the half-cell totally mixing. 25) Determine the cell notation for the redox reaction given below. 3 Cl2(g) + 2 Fe(s) → 6 Cl?(aq) + 2 Fe3+(aq) A) Cl2(g) ? Cl?(aq) ? Pt Fe(s) ? Fe3+(aq) B) Cl?(aq) ? Cl2(g) ? Pt Fe3+(aq) ? Fe(s) C) Fe3+(aq) ? Fe(s) Cl?(aq) ? Cl2(g) ? Pt D) Fe(s) ? Cl2(g) Fe3+(aq) ? Cl?(aq) ? Pt E) Fe(s) ? Fe3+(aq) Cl2(g) ? Cl?(aq) ? Pt 26) What statement is not true about standard electrode potentials? A) E°cell is positive for spontaneous reactions. B) Electrons will flow from more negative electrode to more positive electrode. C) The electrode potential of the standard hydrogen electrode is exactly zero. D) E°cell is the difference in voltage between the anode and the cathode. E) The electrode in any half-cell with a greater tendency to undergo reduction is positively charged relative to the standard hydrogen electrode and therefore has a positive E°. 27) Which of the following is the weakest oxidizing agent? A) H2O2(aq) B) Fe3+(aq) C) ClO2(g) D) F-(s) E) Fe(s) 28) Use the standard half-cell potentials listed below to calculate the standard cell potential for the following reaction occurring in an electrochemical cell at 25°C. (The equation is balanced.) 3 Cl2(g) + 2 Fe(s) → 6 Cl?(aq) + 2 Fe3+(aq) Cl2(g) + 2 e? → 2 Cl?(aq) E° = +1.36 V Fe3+(aq) + 3 e? → Fe(s) E° = -0.04 V A) +4.16 V B) -1.40 V C) -1.32 V D) +1.32 V E) +1.40 V 29) Use the standard half-cell potentials listed below to calculate the standard cell potential for the following reaction occurring in an electrochemical cell at 25°C. (The equation is balanced.) 2F2(g) + Mn(s) → 4 F?(aq) + Mn2+(aq) F2(g) + e? → 2 F?(aq) E° = +2.87 V Mn2+(aq) + 2 e? → Mn(s) E° = -1.18 V A) 1.69 V B) 4.050 V C) -4.050 V D) -4.060 V E) +2.87 V 30) Use the standard half-cell potentials listed below to calculate the standard cell potential for the following reaction occurring in an electrochemical cell at 25°C. (The equation is balanced.) Pb(s) + Br2(l) → Pb2+(aq) + 2 Br?(aq) Pb2+(aq) + 2 e? → Pb(s) E° = -0.13 V Br2(l) + 2 e? → 2 Br?(aq) E° = +1.07 V A) +1.20 V B) +0.94 V C) -0.94 V D) -1.20 V E) -0.60 V