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@X@user.full_name@X@ @GMU: Calculate the [H3O+] of 105.66 mL of a buffer initially consisting of 0.1353 M N2H4 and 0.1741 M N2H5Cl after addition of 0.0022 mol of HCl. Assume that no volume change occurs after addition of the acid. The Kb of N2H4 is 8.90e-7

@X@user.full_name@X@ @GMU: How much time in seconds would it take for a 2.3265 g sample of 18F to decay to a mass of 1.7372 g if it has a half-life of 6.588e3 s.

John Schreifels @GMU: What is the change in mass of 197Au when it is formed from protons, electrons and neutrons if the atom has a mass of 203.97302 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: The reaction below occurs in an electrochemical cell. Which substance would be the best solid electrode in the given half-cell?Pb2+(aq) + Sn(s) → Pb(s) + Sn2+(aq)

@X@user.full_name@X@ @GMU: The vapor pressure of C2H5OH (l) at 320.4 K is 209.7 mm Hg. What is the heat of vaporization if its normal boiling point is 351.6 K?

@X@user.full_name@X@ @GMU: What is the conjugate base and base dissociation constant of H2O2 if its acid dissociation constant is 2.400×10-12 ?

@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 Ni2+(aq) and H+ are 0.164 M and 2.88e-6 M, respectively? The H2(g) pressure is 1 atm at 25oC.2H+(aq) + Ni(s) → Ni2+(aq) + H2(g) Ecoell = 0.260 V

@X@user.full_name@X@ @GMU: What is the rate of consumption of A (M/s), if the rate of consumption of C is 0.326 M/s? Use the reaction below:2A + 3B + 6C → products

@X@user.full_name@X@ @GMU: What is the value of Ksp in water, if 4.63e-6 M of A3B3 dissolves according to the reaction below?A3B3(s)→3A(aq) + 3B(aq) where A and B are ions

@X@user.full_name@X@ @GMU: What is the balanced reaction at the anode for the following galvanic cell?Fe(s) | Fe3+(aq) || Sn2+(aq) | Sn(s)