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@X@user.full_name@X@ @GMU: The pH of a solution of H3O+ was 3.062. What was the hydronium ion concentration?

@X@user.full_name@X@ @GMU: How much energy in kJ is released to form one mole of 116Cd from protons, electrons, and neutrons if the nucleus has a mass of 115.904755 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 is the standard free energy change for the ionization of H2O acid, if its Ka is 1.00e-14.

@X@user.full_name@X@ @GMU: To what temperature would you have to heat bromine, Br2,(l) to cause its vapor pressure to become 402.4 mm Hg if its heat of vaporization and boiling point are 31.40 kJ/mol and 331.9 K, respectively?

@X@user.full_name@X@ @GMU: The pH of a solution of HClO3 was 3.254. What was the hydronium ion concentration?

@X@user.full_name@X@ @GMU: What is the free energy change for the reaction below, if the reaction quotient, Q, at 25.0oC is equal to 1.18e-6?C2H2(g) H2(g) → C2H4(g) ΔGo = -141.144 kJ.

@X@user.full_name@X@ @GMU: When 0.3676 g of citric acid was dissolved in 104.9 mL of water, the osmotic pressure at 26.69°C was 0.4491 atm. What is the formula mass of this compound?

@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 (C9H16(g)) = 484.8200J/mol*K and the heat of formation of C9H16(g)) is 61.8300 kJ/mol?C9H16(g) → 9C(gr) + 8H2(g)

@X@user.full_name@X@ @GMU: RbBr has a face-centered cubic unit cell in which the Br- anions occupy corners and face centers, while the cations fit into the hole between adjacent anions. What is the radius of Rb+ if the ionic radius of Br- is 195.0 pm and the density of RbBr is 3.350 g/cm3?

John Schreifels @GMU: What must the reaction quotient Q be, if the free energy is -1.04e3 kJ at 25.0oC?5C2H2(g) + 6 H2(g) → C10H22(g) ΔGo = -1.01e3 kJ.