Which of the following solutions has the lowest H⁺ concentration?  Hint: Consider the common ion effect and how it would change the percent ionization of the weak acid. 

Consider a 1.00 L buffer solution made with 0.600 mol of HF (Ka = 6.8 × 10⁻⁴) and 0.400 mol of NaF.    What is the pH of the solution after the addition of 0.100 mol of HCl. Hint:  Assume no change in volume upon addition of HCl

Consider the following aqueous reaction between ammonia (NH3) and formic acid (HCOOH): NH3 (aq)  +  HCOOH (aq)   ⇌  NH4+ (aq)  + HCOO─ (aq) Identify the stronger acid and predict whether the equilibrium lies to the left or to the right? Hint: The Ka of HCOOH is 1.8 x 10─4 Hint: The Ka of NH4+ is 5.5 x 10─10

Phophorous-32 decays by beta emission to form sulfur-32.   (In case the picture does not show: The picture indicated that 24 P-32 decayed to 3 P-32 in 18 min. )  What is the decay constant, k, for P-32?

Given the two following reduction half reactions: Al3+(aq) +   3e- →   Al(s)                        Eo = −1.650 V Cd2+(aq) +   2e- →   Cd(s)                      Eo = −0.400 V Calculate ΔGº (in kJ) for a Al/Cd voltaic cell. Hint:  Remembmol)er that a voltaic cell runs on a spontaneous redox reaction.  Hint: Make sure to determine the total moles of electrons transferred for the cell.

Consider the voltaic cell diagram:  Al (s) | Al3⁺(aq) || Ni2⁺ (aq) | Ni (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  

Consider the reaction of elemental bromine with elemental chlorine to make a bromochloride compound at 600 K:                                          Br2(g)  +  Cl2(g)   ⇌   2 BrCl(g)       KP = 81.0 A closed vessel at 600 K is charged with 1.20 atm of Br2(g) and 1.20 atm of Cl2(g) initially and allowed to reach equilibrium. What is the partial pressure of the BrCl (in atm) at that equilibrium?

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

Phophorous-32 decays by beta emission to form sulfur-32.   (In case the picture does not show: The picture indicated that 24 P-32 decayed to 3 P-32 in 6 min. )  What is the decay constant, k, for P-32?

Given the Kc value for the following reaction at a particular temperature:                         SO2 (g) + ½ O2 (g) ⇋ SO3 (g)                  Kc = 4.45 What is the value of Kc for the new equilibrium below at the same temperature?                         2 SO3 (g) ⇋ 2 SO2 (g) + O2 (g)