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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.

At 25°C, the pH of a solution is 7.23.  What is the hydroxide ion concentration, [OH−], of this solution?  

Which of the following has the smallest standard molar entropy, S° (298.15 K)?  

Which of the following combinations, when mixed in equal concentrations in water, would result in a buffer solution?  

If a reaction has a  ΔG = 0, this indicates that:

A 0.085 M solution of acetic acid (CH3COOH)  has a pH of 2.55. What is the percent ionization of this solution?

Consider the reaction of elemental bromine with elemental chlorine to make a bromochloride compound at 600 K:                                        2 BrCl(g)   ⇌   Br2(g)  +  Cl2(g)         KP = 81.0 A closed vessel at 600 K is charged with 3.00 atm of BrCl initially and allowed to reach equilibrium. What is the partial pressure of the Br2 (in atm) at that equilibrium?

A 0.15 M solution of acetic acid (CH3COOH)  has a pH of 2.38. What is the percent ionization of this solution?

A 0.025 M solution of acetic acid (CH3COOH)  has a pH of 2.98. What is the percent ionization of this solution?

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 strongest reducing agent?