Wright CHM 1220 - CHM 1220_ThermodynamicsSolutionsReview_InClass_answers (3 pages)

Previewing page 1 of 3 page document View the full content.
View Full Document

CHM 1220_ThermodynamicsSolutionsReview_InClass_answers



Previewing page 1 of actual document.

View the full content.
View Full Document
View Full Document

CHM 1220_ThermodynamicsSolutionsReview_InClass_answers

19 views


Pages:
3
School:
Wright State University
Course:
Chm 1220 - General Chemistry II

Unformatted text preview:

CHM 1220 In Class Activity Thermodynamics Solutions Review Fall 2017 ANSWERS 1 Estimate the molar heat of vaporization of a liquid whose vapor pressure doubles when the temperature is raised from 85 C to 95 C Clausius Clapyeron equation relates vapor pressure temperature and molar heat of vaporization P H vap 1 1 ln 1 R T2 T1 P2 Rearrange to isolate Hvap plug in values H vap Knowns Unknowns P1 P 1 T1 85 C 358 K P2 2P1 T2 95 C 368 K Hvap P1 P1 J R ln 8 314 ln mol K 2 P P2 1 75 921 10 3 J 75 92 kJ mol mol 1 1 1 1 368 K 358 K T2 T1 2 Hydrogen gas H2 is not abundant in nature but is a useful reagent in the synthesis of liquid methanol from gaseous carbon monoxide The mixture of H2 and CO is often referred to as syngas and is a commonly used in industrial chemistry processes Using the provided thermodynamic data predict under what temperature conditions this reaction is spontaneous 2 H2 g CO g CH3OH l Substance H2 g CO g CH3OH l Hf kJ mol S J mol K 0 130 6 110 5 197 7 238 7 126 8 CHM 1220 In Class Activity Thermodynamics Solutions Review Fall 2017 3 When one mole of solid ammonia melts at its normal melting point 33 34 C in a room maintained at 25 00 C the entropy change of the surroundings is 18 96 J K Estimate the molar entropy of fusion of ammonia at 33 34 C 4 The vapor pressure of benzene C6H6 78 12 g mol at 25 C is 0 1252 atm What is the change in the vapor pressure when 10 00 g naphthalene C10H8 128 2 g mol is dissolved in 0 2000 kg C6H6 CHM 1220 In Class Activity Thermodynamics Solutions Review Fall 2017 5 An aqueous solution of KI has a freezing point of 1 95 C and an osmotic pressure of 25 0 atm at 25 0 C Assuming that KI completely dissociates in water what is the density of the solution 6 Ethylene glycol is used in automobile radiators as an antifreeze Use the following information to determine the freezing point of an antifreeze solution made by mixing 2 5 L of ethylene glycol with 2 5 L of water Ethylene glycol is essentially nonvolatile and it does not dissociate in water molar mass of ethylene glycol 62 1 g mol density of ethylene glycol 1 11 g mL density of water 1 00 g mL Kf for water 1 86 C kg mol DT f K f m 2 5 L ethylene glycol 2 5 L water where m is the molality of ethylene glycol 1000 mL 1 11 g ethylene glycol 1 mol ethylene glycol 44 69 mol ethylene glycol 1L 1 mL ethylene glycol 62 1 mol ethylene glycol 1000 mL 1 00 g water 1 kg



View Full Document

Access the best Study Guides, Lecture Notes and Practice Exams

Loading Unlocking...
Login

Join to view CHM 1220_ThermodynamicsSolutionsReview_InClass_answers and access 3M+ class-specific study document.

or
We will never post anything without your permission.
Don't have an account?
Sign Up

Join to view CHM 1220_ThermodynamicsSolutionsReview_InClass_answers and access 3M+ class-specific study document.

or

By creating an account you agree to our Privacy Policy and Terms Of Use

Already a member?