Blog

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?

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 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.