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Consider the voltaic cell diagram:  Cr(s) | Cr3⁺(aq) || Fe2⁺ (aq) | Fe (s) What is the standard cell potential, E°cell, (in V) for this voltaic cell? Hint: Refer to the table of standard reduction potentials provided. Half Reaction E° red (V) Ag+ (aq)  + e–  →  Ag (s)  +0.80 Fe3+ (aq)  +   e–  → Fe2+ (aq)   +0.77 Cu2+ (aq)  + 2 e–  → Cu (s)    +0.34 Sn4+ (aq) + 2 e–  → Sn2+ (aq)   +0.15 2H+ (aq) + 2 e–  →  H2 (g)  0.00 Pb2+ (aq) + 2 e –  → Pb (s)  –0.13 Sn2+ (aq)  +  2 e–  → Sn (s)  –0.14 Ni2+ (aq) + 2 e –  → Ni (s)   –0.28 Cd2+ (aq) + 2 e –  → Cd (s)   –0.40 Fe2+ (aq) + 2 e –  → Fe (s) –0.44 Cr3+ (aq) + 3 e– →  Cr (s)      –0.74 Zn2+ (aq) + 2 e –  → Zn (s)  –0.76 Al3+ (aq) + 3 e– →  Al (s) –1.66

Given the standard reduction potentials below:  Half Reaction E° red (V) Ag+ (aq)  + e–  →  Ag (s)  +0.80 Fe3+ (aq)  +   e–  → Fe2+ (aq)   +0.77 Cu2+ (aq)  + 2 e–  → Cu (s)    +0.34 Sn4+ (aq) + 2 e–  → Sn2+ (aq)   +0.15 2H+ (aq) + 2 e–  →  H2 (g)  0.00 Pb2+ (aq) + 2 e –  → Pb (s)  –0.13 Sn2+ (aq)  +  2 e–  → Sn (s)  –0.14 Ni2+ (aq) + 2 e –  → Ni (s)   –0.28 Cd2+ (aq) + 2 e –  → Cd (s)   –0.40 Fe2+ (aq) + 2 e –  → Fe (s) –0.44 Cr3+ (aq) + 3 e– →  Cr (s)      –0.74 Zn2+ (aq) + 2 e –  → Zn (s)  –0.76 Al3+ (aq) + 3 e– →  Al (s) –1.66   Which of the following  substances would be the weakest reducing agent?

The base-dissociation constant, Kb , for aniline, C6H5NH2,  is 4.0 x 10-10. The acid-dissociation constant, Ka , for the anilinium ion, C6H5NH3+, is                     .   Hint: All Ka/Kb values are at 25°C.

Consider the titration of 10.0 mL of 0.10 M HClO4 with KOH.   What is the pH after 20.0 mL of 0.35 M KOH has been added?

Complete and balance the following redox half-reaction equation under acidic conditions.     Cr3+(s)   →   CrO42-(aq)       (acidic solution) How many electrons are transfered in this half-reaction when the equation is balanced using the set of smallest whole-number coefficients? 

Consider the following titration curve graphs:   Which plot shows the pH curve expected when HCN is titrated by NaOH ?

Consider the titration of 50.0 mL of 0.10 M HClO4 with KOH.   What is the pH after 20.0 mL of 0.50 M KOH has been added?

Copper metal, Cu (s), is produced by running a current through a solution of Cu2+ in an electrolytic cell. How many grams of copper metal can be deposited from Cu²⁺(aq) when a current of 2.50 A is run for 2.00 h? Hint:  F = 96,500 C/mol e− Hint:  1 A = 1 C/s

The diagrams here represent solutions at various stages in the titration of a weak base B (such as NH3) with HCl. Which image best represents the solution beyond the equivalence point?             

Given the two following reduction half reactions: Fe3+(aq) +  e- →  Fe2+(aq)                  Eo = +0.770 V Pb2+(aq) +   2 e- →   Pb (s)                  Eo = −0.13 V Calculate ΔGº (in kJ) for a Fe2+/Pb voltaic cell. Hint:  Remember that a voltaic cell runs on a spontaneous redox reaction.  Hint: Make sure to determine the total moles of electrons transferred for the cell.