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@X@user.full_name@X@ @GMU: How much energy in kJ is released to form one mole of 123Sb from protons, electrons, and neutrons if the nucleus has a mass of 122.904216 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: Which pair of substances are bases in the reaction below?I- + H3O+ → HI + H2O

@X@user.full_name@X@ @GMU: What is the pH of 4.42e-4 M HNO3 ?

@X@user.full_name@X@ @GMU: NO2 at 354°C decomposes to form NO and O2 according to second order kinetics (see reaction below). The half-life for this reaction was measured to be 1.71e2 s when the initial concentration of NO2 was 3.25e-3 M. What is the rate constant for this reaction?2NO2(g) → 2NO(g) + O2(g)

@X@user.full_name@X@ @GMU: What is the potential of a cell at 25oC for which the reaction below applies, if the molar concentrations of Sn2+(aq) and H+ are 0.100 M and 2.18e-4 M, respectively? The H2(g) pressure is 1 atm at 25oC.2H+(aq) + Sn(s) → Sn2+(aq) + H2(g) Ecoell = 0.140 V

@X@user.full_name@X@ @GMU: What is the value of Ksp in water, if 1.35e-5 M of A2B2 dissolves according to the reaction below?A2B2(s)→2A(aq) + 2B(aq) where A and B are ions

@X@user.full_name@X@ @GMU: Iodine atoms in CCl4 at 25°C react to form molecular iodine according to second order kinetics (see reaction below). The half-life for this reaction was measured to be 3.73e-7 s when the initial concentration of I was 3.27e-4 M. What is the rate constant for this reaction?I + I → I2

John Schreifels @GMU: What is the total entropy change at 25oC for the reaction below, if the standard entropies of reactants and products are So(C(gr)) = 5.74 J/mol*K, So (H2(g)) = 130.68 J/mol*K, and So (C3H8(g)) = 270.2000J/mol*K and the heat of formation of C3H8(g)) is -103.8500 kJ/mol.C3H8(g) → 3C(gr) + 4H2(g)

@X@user.full_name@X@ @GMU: Determine the molality of a 5.664 wt % aqueous solution of NaF.

@X@user.full_name@X@ @GMU: By how much would the rate of reaction (see below) change if the concentration of Cl2 increased by a factor of 1.557. The rate law of this reaction is Rate = k[CHCl3][Cl2]1/2.CHCl3(g) + Cl2(g) → CCl4(g) + HCl(g)