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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.

For the following equilibrium CH4(g)  +   2 H2S(g)   ⇌   CS2(g)   +    4 H2(g) the equilibrium constant, K = 4.28  at 280.0 °C. Which of the following best describes the reaction at equilibrium?

An experimental plot of ln(k) vs. 1/T is obtained in lab for a reaction. The slope of the best-fit line for the graph is -2938 K. What is the value of the activation energy for the reaction in kJ/mol? Hint: The linear form of the Arrhenius equation relates the rate constant to the temperature.

Which of the following will NOT affect the rate of a reaction? temperature of reaction magnitude of enthalpy of reaction (ΔH) concentration of reactants sign of enthalpy of reaction (ΔH) physical state of reactants

An experimental plot of ln(k) vs. 1/T is obtained in lab for a reaction. The slope of the best-fit line for the graph is -3715 K. What is the value of the activation energy for the reaction in kJ/mol? Hint: The linear form of the Arrhenius equation relates the rate constant to the temperature.

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?

Consider the voltaic cell diagram:  Sn(s) | Sn2⁺(aq) || Ag⁺ (aq) | Ag (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  

The combustion of ammonia proceeds by the reaction           4 NH3    +    7 O2  →  4 NO2    +    6 H2O When the rate of appearance of H2O is 1.10 Ms-1, the rate of disappearance of O2 is          Ms-1

A sample of sodium bicarbonate, NaHCO3,  is placed in a closed 1.0 L vessel at 398 K and allowed to decompose unil it reaches equilibrium according to the following equation:                                         2 NaHCO3 (s)   ⇌  Na2CO3(s) +  H2O (g)   +  CO (g)      Kp = 0.450 What is the partial pressure of CO (in atm)  at equilibrium?

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 9min. )  What is the decay constant, k, for P-32?