@X@user.full_name@X@ @GMU: When 3.320 g of urea was dissolved in 102.4 g of benzene, the boiling point was 354.6 K. What is the formula mass of this compound? The boiling point elevation constant for benzene is 2.53 (°C*kg)/mol. The melting point and boiling points are 5.50°C and 80.10°C, respectively.

@X@user.full_name@X@ @GMU: Initially there were equilibrium concentrations of 0.1328 M A, 0.3333 M B, and 0.1328 M C (see reaction below). The concentration of C was suddenly increased to 11.80 M. What was the approximate concentration of each after equilibrium had been re-established?4A → 3 B +2 C Kc = 1.004

@X@user.full_name@X@ @GMU: The osmotic pressure of an unknown solution is 0.684 atm at 34.21 °C. Which of the solutions below is the most likely one? Assume any salt is completely ionic!

@X@user.full_name@X@ @GMU: What is the value of Kc at 450.00 °C for the reaction below if Kp is 1.22e-3 at this temperature?N2(g) + 3H2(g) → 2NH3(g)

@X@user.full_name@X@ @GMU: Determine the mole fraction of toluene if 6.1017 g of toluene, C7H8, was mixed with 7.48 g of cyclohexene, C6H10. MW(C7H8) = 92.141 g/mol; MW(C6H10) = 82.145 g/mol.

@X@user.full_name@X@ @GMU: When 12.26 g of citric acid was dissolved in 108.4 g of benzene, the freezing point was 275.6 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.

@X@user.full_name@X@ @GMU: Determine the rate of the last set of reaction conditions. [A]o [B]o Rate, M/s 0.281 0.289 3.71e-5 0.433 0.289 7.08e-5 0.281 0.531 5.03e-5 0.433 0.444 ?

@X@user.full_name@X@ @GMU: The osmotic pressure of an unknown solution is 0.516 atm at 10.37 °C. Which of the solutions below is the most likely one? Assume any salt is completely ionic!

@X@user.full_name@X@ @GMU: Radioactive substances decay by first-order kinetics. How many days would be required for a sample containing neptunium-93 to decrease to 66.22% of its initial activity? The half-life of neptunium-93 is 2.35 days.

@X@user.full_name@X@ @GMU: Initially there were equilibrium concentrations of 0.1041 M A, 0.3333 M B, and 0.1041 M C. Which change will cause Qc to be greater than Kc? Use the reaction below.5A → 3 B +3 C Kc = 0.904