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1.292 K2.315 K3.216 K4.107 K5.136 KcorrectExplanation:Follow the 1 atm line horizontally to thesolid/liquid line and read from the tempera-ture scale≈136 K.023(part 2 of 3) 10 pointsIn the previous phase diagram, the three zonesthat are depicted as I, II, and III are which ofthe following?1.I-liquid; II-gas; III-solid2.I-vapor; II-solution; III-blend3.I-solid; II-liquid; III-gas4.I-gas; II-solid; III-plasma5.I-liquid; II-solid; III-gascorrectExplanation:Zone II is solid, zone III is gas, and zone Iis liquid.024(part 3 of 3) 10 pointsReferring to the same phase diagram, the sub-stance is heated from 100 K to 300 K at apressure of 50 atm.Which of the followinghappens to the substance?1.sublimation2.deposition3.vaporization4.fusion and sublimation5.condensation6.fusion7.sublimation and vaporization8.condensation and vaporization9.solidification10.melting and vaporizationcorrectExplanation:The solid/liquid line is crossed, so meltingoccurs. Then the liquid/gas line is crossed, sovaporization occurs.025(part 1 of 1) 10 pointsWhich of the following statements about col-ligativepropertiesofaqueoussolutions isFALSE?1.The higher the concentration of solute inthe solution, the higher the vapor pressure ofthe solvent.correct2.Osmosis is a colligative property.3.Colligative properties only depend on thenumber of solute particles present in solu-tion.4.For a given solution, the freezing pointwill be lowered more than the boiling pointwill be raised.
Yoon, Seong Meen – Exam 1 – Due: Sep 18 2007, 3:00 pm – Inst: James Holcombe9Explanation:Colligative properties, which include osmo-sis, vapor pressure lowering, melting and boil-ing point elevations, depend only on the num-ber of solute particles present in solution, noton their properties. The effect on the meltingpoint of a given solution is less than the effecton its boiling point.With a higher concentration of non-volatilesolute the concentration of the solvent in thesolution is lower, causing the vapor pressureof the solution to be lower.026(part 1 of 1) 10 pointsHenry’s Law would allow one to predict1.the extent of dissociation of solute insolution.2.elevation in boiling point with the addi-tion of a non-volatile solute.3.the new pressure of a gas if only thevolume of the vessel containing the gas werechanged.4.the vapor pressure of the solvent abovethe pure solvent.5.the solubility of a gas in a liquid given thepressure of gas above the solution.correctExplanation:Henry’s law states that the pressure of a gasabove the surface of a solution is proportionalto the concentration of gas dissolved in thesolution.027(part 1 of 1) 10 pointsIn discussions of global warming, CO2andH2O are considered “greenhouse gases” be-cause1.together they make up a major portion (>50%) of the atmosphere above the planet.