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Venous ulcers occur more frequently on the ankles rather than the thighs due to _____________. 

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

Methane gas can be produced by the reaction of solid carbon with hydrogen gas as follows                     C(s)   +   2 H2(g)  ⇌   CH4(g) For this reaction at equilibrium, Kp =  0.38.  A vessel containing carbon is sealed and injected inititally with hydrogen to a pressure of 2.0 atm and with methane to a pressure of 2.0 atm. What happens as the reaction proceeds toward equilibrium?  Hint:  this is a K vs Q question.  Which way will the reaction proceed to reach equilibrium?

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?