Consider the following electrochemical cell:Pt|H,(8,p°)|HCI(aq,b)|Hg.Cl,(s)|Hg()The potential of this cell, in relation to different molalities (b), has been measured with high precision at25°C. The following results have been obtained:b/mmol.kgE/VI (ionic strength)Y: (DHLL)|Y: (linear fit)1.60773.07695.04037.693810.94740.600800.568250.543660.522670.50532(i)Write the half-reactions for the cell, and show the standard potential of each half-reaction.(ii)Determine the standard cell potential through simple calculation.

In a cell notation, the left-side represents the oxidation-half reaction and the right side…

Consider the following electrochemical cell: Pt|H,(8,p°)|HCI(aq.b)|H8.C1,(s)|Hg() The potential of this cell, in relation to different molalities (b), has been measured with high precision at 25°C. The following results have been obtained: b/mmol.kg E/V | (ionic strength) Y: (DHLL) [Y: (linear fit) 1.6077 0.60080 3.0769 5.0403 0.54366 7.6938 10.9474 0.56825 0.52267 0.50532 (1) Write the half-reactions for the cell, and show the standard potential of each half-reaction. (ii) Determine the standard cell potential through simple calculation.

Consider the following electrochemical cell: Pt|H,(8,p°)|HCI(aq.b)|H8.C1,(s)|Hg() The potential of this cell, in relation to different molalities (b), has been measured with high precision at 25°C. The following results have been obtained: b/mmol.kg E/V | (ionic strength) Y: (DHLL) [Y: (linear fit) 1.6077 0.60080 3.0769 5.0403 0.54366 7.6938 10.9474 0.56825 0.52267 0.50532 (1) Write the half-reactions for the cell, and show the standard potential of each half-reaction. (ii) Determine the standard cell potential through simple calculation.

Chemistry: The Molecular Science

5th Edition

ISBN:9781285199047

Author:John W. Moore, Conrad L. Stanitski

Publisher:John W. Moore, Conrad L. Stanitski

Chapter17: Electrochemistry And Its Applications

Section: Chapter Questions

Problem 38QRT

See similar textbooks

Similar questions

For each of the following reactions, determine the overall balanced electrochemical reaction, its standard electric potential, and the standard Gibbs energy of the reaction. aCo+F2Co2++2F bZn+Fe2+Zn2++Fe c Zn+Fe3+Zn2++Fe d Hg2++HgHg22+
Table 17-1 lists common half-reactions along with the standard reduction potential associated with each half-reaction. These standard reduction potentials are all relative to some standard. What is the standard (zero point)? lf is positive for a half-reaction, what does it mean? If is negative for a half-reaction, what does it mean? Which species in Table 17-1 is most easily reduced? Least easily reduced? The reverse of the half-reactions in Table 17-1 are the oxidation half-reactions. How are standard oxidation potentials determined? In Table 17-1, which species is the best reducing agent? The worst reducing agent? To determine the standard cell potential for a redox reaction, the standard reduction potential is added to the standard oxidation potential. What must be true about this sum if the cell is to be spontaneous (produce a galvanic cell)? Standard reduction and oxidation potentials are intensive. What does this mean? Summarize how line notation is used to describe galvanic cells.
For each of the reactions, calculate E from the table of standard potentials, and state whether the reaction is spontaneous as written or spontaneous in the reverse direction under standard conditions. (a) Zn(s)+Fe2+(aq)Zn2+(aq)+Fe(s) (b) AgCl(s)+Fe2+(aq)Ag(s)+Fe3+(aq)+Cl(aq) (c) Br2(l)+2Cl(aq)Cl2(g)+2Br(aq)
Halide ions can he deposited at a silver anode, the reaction being Ag(s) + X- AgX(s) +e- Suppose that a cell was formed by immersing a silver anode in an analyte solution that was 0.0250 M Cl-,Br-, and I -ions and connecting the half-cell to a saturated calomel cathode via a salt bridge. (a) Which halide would form first and at what potential? Is the cell galvanic or electrolytic? (b) Could I- and Br- be separated quantitatively? (Take 1.00 l0-5 M as the criterion for quantitative removal of an ion.) If a separation is feasible, what range of cell potential could he used? (c) Repeat part (b) for I- and Cl-. (d) Repeat part (b) for Br- and Cl-.
One ecologically important equilibrium is that between carbonate and hydrogencarbonate (bicarbonate) ions in natural water. (a) The standard Gibbs energies of formation of CO32−(aq) and HCO3−(aq) are −527.81 kJ mol−1 and −586.77 kJ mol−1, respectively. What is the standard potential of the HCO3−/CO32−,H2 couple? (b) Calculate the standard potential of a cell in which the cell reaction is Na2CO3(aq) + H2O(l) → NaHCO3(aq) + NaOH(aq). (c) Write the Nernst equation for the cell, and (d) predict and calculate the change in cell potential when the pH is changed to 7.0 at 298 K.
If a dilute H2 SO4 solution is electrolyzed with copper electrodes, the most likely electrode reactions are 2H ^ + + 2e- = H2 (g) at the cathode and 2Cu (s) + H2O = Cu2O (s) + 2H ^ + + 2e- at the anode. If we observe the formation of 27.4 cm3 of moist hydrogen (751 barometric torrs, 23.3 ° C) at the cathode, what change in weight will there be simultaneously at the anode? Data: Pv H2O 23.3 ° C = 22 torr.Atomic mass: Cu (65); O (16); H (1)
One ecologically important equilibrium is that between carbonate and hydrogencarbonate (bicarbonate) ions in natural water. (a)The standard Gibbs energies of formation of CO32-(aq) and HCO3-(aq) are -52781 kJ mol-1, and -586.77 kJ mol-1, respectively. What is the standard potential of the HCO3-/CO3-,H2 couple? (b) Calculate the standard potential of a cell in which the cell reaction is Na2CO3(aq) + H2O(I) → NaHCO3(aq) + NaOH(aq). (c) Write the Nernst equation for the cell and (d) predict and calculate the change in potential when the pH is changed to 7.0. (e) Calculate the value of pKa for HCO3-(aq).
The standard cell potential of a Daniell cell, with cell reactionZn(s) + Cu2+(aq) → Zn2+(aq) + Cu(s), is 1.10 V at 25 °C.Calculate the corresponding standard reaction Gibbs energy.
A fuel cell develops an electric potential from the chemical reaction between reagents supplied from an outside source. What is the potential of a cell fuelled by (a) hydrogen and oxygen, (b) the complete oxidation of benzene at 10 bar and 298 K?
Consider a hydrogen electrode in H Br(aq) at 25 °C operating at 145 bar. Estimate the change in the electrode potential when the solution is changed from 5.0 mmol dm-3 to 15.0 mmol dm-3.
The standard potential of a Daniell cell, with cell reaction Zn(s) + Cu2+(aq) → Zn2+(aq) + Cu(s), is 1.10 V at 25 °C. Calculate the corresponding standard reaction Gibbs energy.
The standard electromotive force of the cell Pt(s)|H2(g)|HCl(aq)|AgCl(s)|Ag(s) has been determined from 0°C to 90°C, and the data were found to fit the expression E/V = 0.237 – 4.856 × 10−4T(°C) − 3.421 × 10−6T2(°C) + 5.869 × 10−9T3(°C) Calculate the equilibrium constant, the standard reaction Gibbs energy, entropy and enthalpy for the cell reaction at 25°C. F = 96485 C mol-1 AgCl(s) + ½H2(g) → Ag(s) + HCl(aq)