You are given a solution of anthracene (a non-electrolyte solute, 178.23 g/mol) in benzene (78.11 g/mol, C6H6). The freezing point of this solution is 0.00oC. What is the vapor pressure (torr) of this solution, if anthracene has no vapor pressure (in other words, if anthracene is non-volatile)? For grading purposes, please report the calculated pressure to 3 significant figures. For pure benzene: vapor pressure at 25oC equal 97.7 torr; freezing point is 5.51oC, and Kf = 5.12oC/m. Hint: Assume 1 kg solvent. How is total vapor pressure related to mole fraction?

Urea (molar mass: 60.056 g/mol) is a non-volatile solute with a solubility of 17.0 g per 100 mL of methanol at 20 ºC. The vapor pressure of pure methanol (molar mass: 32.042 g/mol; density: 0.792 g/mL) at 20 ºC is 95.7 torr. What is the vapor pressure of a saturated solution of urea in methanol at 20 ºC? Select one: a.5.00 torr b.9.83 torr c.85.9 torr d.55.6 torr

1.613 g sample of an unknown nonionizing molecular compound is added to 250.0 g of benzene(C6H6, MW = 78.11 g/mol). The normal freezing point of the solution is 0.17 C lower than the normalfreezing point of pure benzene. Based on this information, find the molecular weight of the unknowncompound. benzene =  Kf = 5.12 kg x Degrees C/mol.

Pentane (C5H12) and hexane (C6H14) form an ideal solution. At 25°C the vapor pressures of pentane and hexane are 511 and 150 torr, respectively. A solution is prepared by mixing 25 mL pentane (density, 0.63 g/mL) with 43 mL hexane (density, 0.66 g/mL).   What is the vapor pressure of the resulting solution? Ptotal=         torr   What is the composition by the mole fraction of pentane in the vapor that is in equilibrium with this solution?

Determine the freezing point depression of a solution that contains 30.7 g glycerin (C 3H 8O 3, molar mass = 92.09 g/mol) in 376 mL of water. Some possibly useful constants for water are K f = 1.86°C/ m and K b = 0.512°C/ m.        2.18°C        0.654°C        3.33°C        1.65°C        0.887°C

Biphenyl, C1,H10, is a nonvolatile, nonionizing solute that soluble in benzene, C,H6. At 25 °C, the vapor pressure of pure benzene is 100.84 Torr. What is the vapor pressure of a solution made from dissolving 17.8 g of biphenyl in 30.3 g of benzene? Psolution Torr II

1. Suppose that you add 27.5 g of an unknown molecular compound to 0.250 kg of benzene, which has a Kf of 5.12 oC/m. With the added solute, you find that there is a freezing point depression of 3.58 oC compared to pure benzene. What is the molar mass (in g/mol) of the unknown compound? 2. What is the freezing point (in degrees Celcius) of 3.70 kg of water if it contains 187.4 g of CaBr2? The freezing point depression constant for water is 1.86 oC/m and the molar mass of CaBr2 is 199.89 g/mol. 3. What mass, in grams, of NaCl needs to be added to 1.6 kg of water in order to create a solution with a freezing point of -5.6 °C? The freezing point depression constant of water is 1.86 ºC/m.

When 14.4 g14.4 g of an organic compound known to be 55.81% C55.81% C, 7.0% H7.0% H, and 37.17% O37.17% O by mass is dissolved in 825.8 g825.8 g of benzene, the freezing point is 4.80 ∘C4.80⁢ ∘C. The normal freezing point of benzene is 5.49 ∘C5.49⁢ ∘C. What is the molecular formula for the organic compound? Assume that the organic compound is a molecular solid and does not ionize in water. ?fKf values for various solvents are given in the colligative constants table. molecular formula: CHO