Devise electrochemical cells in which the following reactions could be made to occur. If liquid junctions are necessary, note them in the cell schematic appropriately, but neglect their effects. (a) H2OH + OH¯ (b) 2H2O2 H₂O (c) 2PbSO4 + 2H2O (d) An TMPD PыO₂+ Pb + 4H+ + 20%¯¯ An + TMPD (in acetonitrile, where An and An are anthracene and its anion radical, and TMPD and TMPD are N,N,N',N'-tetramethyl-p-phenylenediamine and its cation radical. Use anthracene potentials for DMF solutions given in Appendix C.3). (e) 2Ce3+ + 2H + BQ 2Ce4+ + H2Q (aqueous, where BQ is p-benzoquinone and H₂Q is p- hydroquinone) (f) Ag +Agl (aqueous) (g) Fe3+ + Fe(CN)6 Fe²+ + Fe(CN) (aqueous)

A 0.0712-g sample of a purified organic acid was dissolved in an alcohol-water mixture and titrated with coulometrically generated hydroxide ions. With a current of 0.0392 A, 241 s was required to reach aphenolphthalein end point. Calculate the equivalent mass of the acid.

What is the cell potential of the following cell at 25C? Ni(s)Ni2+(1.0M)Sn2(1.5104M)Sn(s)

The cell potential of the following cell at 25C is 0.480 V. ZnZn2+(1M)H+(testsolution)H2(1atm)Pt What is the pH of the test solution?

A typical total phosphate concentration in a cell, [HPO42] + [H2PO4], is 2.0 102 M. What are the concentrations of HPO42 and HPO4 at pH 7.40?

What is the standard cell potential you would obtain from a cell at 25C using an electrode in which I(aq) is in contact with I2(s) and an electrode in which a chromium strip dips into a solution of Cr3(aq)?

Calculate the cell potential of a cell operating with the following reaction at 25C, in which [Cr2O32] = 0.020 M, [I] = 0.015 M, [Cr3+] = 0.40 M, and [H+] = 0.60 M. Cr2O72(aq)+6I(aq)+14H+(aq)2Cr3+(aq)+3I2(s)+7H2O(l)

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.

B. If the following half-cells are the right-hand elec- trode in a galvanic cell with a standard hydrogen electrode on the left, calculate the cell potential. If the cell were shorted, indicate whether the electrodes shown would act as an anode or a cathode. (a) Ni Ni (0.0883 M) (b) Ag|Agl(sat'd), KI(0.0898 M) (c) Pr|O,(780 torr), HCl(2.50 X 10 M)

. (a) Balance the following simple redox reaction.Fe (s) + O2(g) + 2H2O (l) → Fe3+ + 4 OH- (3)(b) If the standard change in the Gibbs energy of the molar reaction in part (a) is-507.13 kJ. Calculate the cell potential of the reaction.