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@X@user.full_name@X@ @GMU: Initially there were equilibrium concentrations of 0.3421 M A, 0.2341 M B, and 0.1120 M C. Which change will cause the equilibrium to shift from right to left if the reaction is exothermic? Use the reaction below.4A(aq) → 4 B(aq) +3 C(aq) K = 1.003

@X@user.full_name@X@ @GMU: What is the rate of consumption of A (M/s), if the rate of consumption of B is 0.345 M/s? Use the reaction below:3A + 4B + 5C → products

@X@user.full_name@X@ @GMU: Uranium -238 decays in a series of steps to Pb-206. When the material is very old, one can treat the kinetics as a decay directly to Pb and the ratio of these two can be treated as a measure of the age of a rock. A rock containing 238U and 206Pb was examined to determine its approximate age. The molar ratio of 206Pb to 238U was 0.1246. Assuming no lead was originally present and that all lead formed remained in the rock, what is the age of the rock (in years)? The half-life of 238U is 4.50e9 yr.

@X@user.full_name@X@ @GMU: The cell potential was -0.109 V at 25oC and a Ni2+(aq) concentration of 0.199 M. What was the hydronium ion concentration? The H2(g) pressure was 1 atm at 25oC.2H+(aq) + Ni(s) → Ni2+(aq) + H2(g) Ecoell = 0.260 V

John Schreifels @GMU: What is the change in mass of 133Cs when it is formed from protons, electrons and neutrons if the atom has a mass of 132.905429 amu? The masses of the proton, electron and neutron are 1.00728 amu, 0.000549 amu and 1.00867 amu, respectively.

@X@user.full_name@X@ @GMU: What would the pOH be after addition of 16.54 mL of 0.1000 M NaOH to 25.00 mL of 0.1000 HA (a weak acid, Ka = 9.23e-5)?

@X@user.full_name@X@ @GMU: What would the pOH be after addition of 9.97 mL of 0.1000 M NaOH to 25.00 mL of 0.1000 HA (a weak acid, Ka = 6.08e-4)?

@X@user.full_name@X@ @GMU: What is the coefficient, b, in the reaction below, if Kc = 1.65e-5 and Kp = 3.39e-7 at 320.84°C?3A(s) + bB(g) → 3C(g)

@X@user.full_name@X@ @GMU: The osmotic pressure of a 13.075 mM solution of K3PO4 is 0.966 atm at 14.38 °C. How many ions per formula unit of K3PO4 must there be? The compound may not be completely ionic.

@X@user.full_name@X@ @GMU: The osmotic pressure of an unknown solution is 747.829 mm Hg at 29.14 °C. Which of the solutions below is the most likely one? Assume any salt is completely ionic!