@X@user.full_name@X@ @GMU: BaO has a face-centered cubic unit cell in which the O2- anions occupy corners and face centers, while the cations fit into the hole between adjacent anions. What is the radius of Ba2+ if the ionic radius of O2- is 140.0 pm and the density of BaO is 5.720 g/cm3?

@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 Cu2+(aq) and H+ are 0.127 M and 2.19e-4 M, respectively? The H2(g) pressure is 1 atm at 25oC.2H+(aq) + Cu(s) → Cu2+(aq) + H2(g) Ecoell = -0.340 V

@X@user.full_name@X@ @GMU: Calculate the [OH-] of 114.93 mL of a buffer initially consisting of 0.1796 M CH3NH2 and 0.1900 M CH3NH3Br after addition of 0.00363 mol of HCl. Assume that no volume change occurs after addition of the acid. The Kb of CH3NH2 is 3.70e-4

@X@user.full_name@X@ @GMU: What is the pOH of 9.35e-4 M HNO3 ?

@X@user.full_name@X@ @GMU: After 62.896 seconds 45.59 % of A had not reacted. What is the first order rate constant?

@X@user.full_name@X@  @GMU: When 10.59 g of citric acid was dissolved in 107.4 g of benzene, the freezing point was 276.0 K. What is the formula mass of this compound? The freezing point depression constant for benzene is 5.12 (°C*kg)/mol. The melting point and boiling points are 5.50°C and 80.10°C, respectively.

John Schreifels @GMU: What is the balanced reaction at the anode for the following galvanic cell?Sn(s) | Sn2+(aq) || Cu+(aq) | Cu(s)

@X@user.full_name@X@ @GMU: How much time in days would it take for a 1.4017 g sample of 233Pa to decay to a mass of 0.9045 g if it has a half-life of 5.417e6 s.

@X@user.full_name@X@ @GMU: What is the standard free energy change for the following cell?2Cu+(aq) + Ni(s) → 2Cu(s) + Ni2+(aq) Ecoell = 0.780V

@X@user.full_name@X@ @GMU: What is the rate of consumption of C (M/s), if the rate of consumption of A is 0.231 M/s? Use the reaction below:2A + 3B + 4C → products