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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 in the buffer zone between the initial and equivalence points?                                                               

What is the molar solubility (in M) of manganese (II) hydroxide, Mn(OH)2, in water? Hint:  Ksp of Mn(OH)₂ is 2.1 × 10-13  

The reaction A(g) + B(g) → C(l) is shown to be endothermic. Which of the following is true concerning the reaction?

Consider the following voltaic cell with the overall cell reaction: Zn (s)   +   2 H+ (g)  ⟶ Zn2+ (g)   +    H2 (g) If the pressure of H2 gas is increased in the cathode cell, the value of Q will                  and the value of Ecell will                   .

Consider the titration of 25.0 mL of 0.10 M HClO4 with KOH.   What is the pH after 20.0 mL of 0.40 M KOH has been added?

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?