1.3 Pentane (C5H12) and hexane (C6H14) form an ideal solution. The vapor pressures of pentane and hexane at 25 °C are 511 torr and 150 torr, respectively. If the mole fraction of hexane in a pentane-hexane solution is 0.50, what is the mole fraction of pentane in the vapor that is in equilibrium at 25 °C with this solution. a) 0.23 b) 0.77 c) 0.89 d) 0.50 e) none of these 1.4 The solubility of the salt MrAy is 1.0 x 10-2 mol/L at 25°C. The osmotic pressure exhibited by a solution saturated with MrAy at 25°C is 1.22 atm. Determine the values of x and y by assuming ideal behavior. a) x=1, y =3 b) x = 2, y = 5 c) x = 1, y = 1 d) x = 2, y = 3 e) none of these 1.5 A 50.00 g sample of a compound dissolved in 0.500 kg of chloroform (which boils at 61.2 °C and has Kb= 3.63 °C kg/mole) is found to elevate the boiling point of the solution by 2.50 °C. What is the molecular mass of the solute? (assume i=1) a) 70.6 g/mole b) 145 g/mole c) 145.2 g/mole d) 245 g/mole e) none of these

1.3 Pentane (C5H12) and hexane (C6H14) form an ideal solution. The vapor pressures of pentane and hexane at 25 °C are 511 torr and 150 torr, respectively. If the mole fraction of hexane in a pentane-hexane solution is 0.50, what is the mole fraction of pentane in the vapor that is in equilibrium at 25 °C with this solution. a) 0.23 b) 0.77 c) 0.89 d) 0.50 e) none of these 1.4 The solubility of the salt MrAy is 1.0 x 10-2 mol/L at 25°C. The osmotic pressure exhibited by a solution saturated with MrAy at 25°C is 1.22 atm. Determine the values of x and y by assuming ideal behavior. a) x=1, y =3 b) x = 2, y = 5 c) x = 1, y = 1 d) x = 2, y = 3 e) none of these 1.5 A 50.00 g sample of a compound dissolved in 0.500 kg of chloroform (which boils at 61.2 °C and has Kb= 3.63 °C kg/mole) is found to elevate the boiling point of the solution by 2.50 °C. What is the molecular mass of the solute? (assume i=1) a) 70.6 g/mole b) 145 g/mole c) 145.2 g/mole d) 245 g/mole e) none of these

Chemistry by OpenStax (2015-05-04)

1st Edition

ISBN:9781938168390

Author:Klaus Theopold, Richard H Langley, Paul Flowers, William R. Robinson, Mark Blaser

Publisher:Klaus Theopold, Richard H Langley, Paul Flowers, William R. Robinson, Mark Blaser

Chapter16: Thermodynamics

Section: Chapter Questions

Problem 51E: In the laboratory, hydrogen chloride (HCl(g)) and ammonia (NH3(g)) often escape from bottles of...

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