100%(1)1 out of 1 people found this document helpful
This preview shows page 4 - 7 out of 11 pages.
1. the same. CORRECT2. larger.3. smaller.Explanation:Once a solution is saturated in a solute, nochange in the amount that will enter to thesolution will occur.0142.9pointsDissolving ionic salts in water does not al-ways cause an increase in the entropy of thesystem.Which statement best explains thisobservation?
Version 023 – Exam 1 – holcombe – (51395)What is the effective molarity (i.e., molarityof “particles” such as cations, anions,etc.)responsible for this osmotic pressure from thenatural water from the local stream? You canassume the van’t Hoff factor is one.C. Assume the enthalpy of vaporiza-tion of water is independent of temperature.4.503 torrcorrect5.256 torrExplanation:T1= 37◦C + 273.15 = 310.15 KT2= 87◦C + 273.15 = 360.15 KΔH◦vap= 44.0 kJ·mol−1P1= 47.1 torrUsing the Clausius-Clapeyron equation,lnparenleftbiggP2P1parenrightbigg=ΔH◦vapRparenleftbigg1T1-1Tparenrightbigg2=44 kJ·mol−18.314 J/mol−1·K−1·1000 J1 kJ×parenleftbigg1310.15 K-1360.15 Kparenrightbigg= 2.36896P2P1=e2.36896P2=P1e2.36896= (47.1 torr)e2.36896= 503.323 torr0172.9points0182.9pointsWhich of the following would raise the vaporpressure of a sample of hexane in a closedcontainer?I) adding more liquid to the containerII) decreasing the size of the containerIII) adding a non-volatile solute to the liquid1.I only2.II and III3.nonecorrect
Version 023 – Exam 1 – holcombe – (51395)64.I and II5.II only6.III only