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@X@user.full_name@X@ @GMU: What is the standard free energy change for the following cell?3Sn2+(aq) + 2Al(s) → 3Sn(s) + 2Al3+(aq) Ecoell = 1.520V

@X@user.full_name@X@ @GMU: To what temperature would you have to heat methanol, CH3OH,(l) to cause its vapor pressure to become 423.3 mm Hg if its heat of vaporization and boiling point are 37.40 kJ/mol and 338.1 K, respectively?

@X@user.full_name@X@ @GMU: The cell potential was -0.377 V at 25oC and a Sn4+(aq) concentration of 0.145 M. What was the hydronium ion concentration? The H2(g) pressure was 1 atm at 25oC.2H+(aq) + Sn2+(aq) → Sn4+(aq) + H2(g) Ecoell = -0.150 V

@X@user.full_name@X@ @GMU: What is the concentration of OH- in 0.1232 M H2CO3 ? See reaction belowH2CO3 + H2O → HCO-3 + H3O+ Ka = 4.300×10-7

@X@user.full_name@X@ @GMU: Initially there were equilibrium concentrations of 0.3387 M A, 0.2024 M B, and 0.1151 M C. Which change will cause the equilibrium to shift from left to right if the reaction is endothermic? Use the reaction below.5A(aq) → 3 B(aq) +2 C(aq) K = 0.999

@X@user.full_name@X@ @GMU: What is the pOH of a 0.1275 M HNO2 ? See reaction belowHNO2 + H2O → NO-2 + H3O+ Ka = 4.600×10-4

@X@user.full_name@X@ @GMU: What is the temperature at which the reaction below becomes spontaneous, if the standard entropies of reactants and products at 25oC are So (C(gr)) = 5.74 J/mol*K, So(H2(g)) = 130.68 J/mol*K, and So (C7H14(g)) = 424.5800J/mol*K and the heat of formation of C7H14(g)) is -62.1600 kJ/mol?C7H14(g) → 7C(gr) + 7H2(g)

@X@user.full_name@X@ @GMU: How much time in minutes would it take for a 2.4869 g sample of 235U to decay to a mass of 1.7354 g if it has a half-life of 7.800e8 s.

@X@user.full_name@X@ @GMU: Which pair of substances are bases in the reaction below?ClO-4 + HClO → HClO4 + ClO-

@X@user.full_name@X@ @GMU: What is the pOH of 1.11e-3 M HCl?