The term proof is defined as twice the percent by volume of pure ethanol in solution. Thus, a solution that is 95% (by volume) ethanol is 190 proof. What is the molarity of ethanol in a 94 proof ethanol–water solution? Assume the density of ethanol, C2H5OH is 0.79 g/cm3 and the density of water is 1.0 g/cm3 and volumes are additive

A solution is composed of 1.40 mol cyclohexane (P∘cy=97.6 torrPcy∘=97.6 torr) and 2.50 molmol acetone (P∘ac=229.5 torr). What is the total vapor pressure Ptotal above this solution?

The normal freezing point of a certain liquid X is 0.60°C, but when 0.14 kg of barium hydroxide (BaOH2) are dissolved in 900.g of X the solution freezes at −1.6°C instead. Use this information to calculate the molal freezing point depression constant Kf of X. Round your answer to 2 significant digits.

The dispersed phase of a certain colloidal dispersion consistes of spheres of diameter 1.0 x 102 nm. What are the volume and surface area of each sphere? V = _ and SA = _ How many spheres are required to give a total volume of 1.0 cm3? What is the total surface area of these spheres in square meters? _ spheres, total SA = _ m2 The dispersed phase of a certain colloidal dispersion consistes of spheres of diameter 1.0 x 102 nm.

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?

A student dissolves 20. g of benzoic acid (C,H,O,) in 125. mL of a solvent with a density of 1.07 g/mL. The student notices that the volume of the solvent does not change when the benzoic acid dissolves in it. Calculate the molarity and molality of the student's solution. Be sure each of your answer entries has the correct number of significant digits. molarity Ox10 molality %D

The solubility of a compound (molar mass = 175 g/mol) in water is found to be 7.75 grams per 100.0 grams of water at 25oC.  Calculate the molality of the compound in a saturated aqueous solution at 25oC.  Your answer should have 3 significant figures.  Do not include the units with your answer, but the units should be molality.

A solution of 0.890 g of an organic compound in 100.0 g of benzene has a freezing point of 5.107°C. What are the molality of the solution and the molar mass of the solute? The normal freezing point of benzene is 5.500°C and the Kf for benzene is 5.12°C/m. molality molar mass = g/mol

Automotive antifreeze consists of ethylene glycol, C₂H6O2, a non volatile nonelectrolyte. Calculate the boiling point and freezing point of a 25% mass percent solution of ethylene glycol in water. MW of Ethylene Glycol: 62.07 g/mol Kb Water: 0.52 °C/m K Water: 1.86 °C/m. 50. What is the molarity of the solution? Answer: 51. What is the change in freezing point temperature (in °C) of ethylene glycol solution? Answer: 52. What is the change in boiling point temperature (in °C) of ethylene glycol solution? Answer: 53. What is the boiling point temperature of the ethylene glycol solution? Answer: 54. What is the freezing point temperature of the ethylene glycol solution? Answer:

A solution made by dissolving 150.0 g of an unknown compound in 425.0 mL of benzene to make a solution which has a freezing point 18.6 °C lower than that of pure benzene. Kf for benzene is 5.12 °C/m and the density of benzene is 0.877 g/mL.     What was the molality of the solution?   How many moles of the unknown compound were dissolved in the solution?   What is the molar mass of the unknown compound?