Chemistry: Principles and Practice
Chemistry: Principles and Practice
3rd Edition
ISBN: 9780534420123
Author: Daniel L. Reger, Scott R. Goode, David W. Ball, Edward Mercer
Publisher: Cengage Learning
bartleby

Concept explainers

bartleby

Videos

Question
Book Icon
Chapter 12, Problem 12.85QE

(a)

Interpretation Introduction

Interpretation:

The mole fraction of heptane and hexane in liquid phase has to be given.

Concept Introduction:

Mole fraction:  Mole fraction of a substance in a solution is the number of moles of that substance divided by the total number of moles of all substances present.  The formula is,

  χA=MolesofA (inmol)MolesofA (in mol) +MolesofB (in mol) +MolesofC (in mol) +...χA=MolesofA (inmol)Totalnumberofmolesofcomponents(inmol)

(a)

Expert Solution
Check Mark

Answer to Problem 12.85QE

The mole fraction of hexane is 0.4658.

The mole fraction of heptane is 0.5342.

Explanation of Solution

Given,

Weight of hexane        =15.0g

Weight of heptane        =20.0g

Vapor pressure of hexane    =278torr

Vapor pressure of heptane    =92.3torr

The moles of heptane and hexane are calculated from their molar masses respectively.

  Moles of hexane=15g×1mol86.18g=0.1740mole

  Moles of heptane=20g×1mol100.21g=0.1995mole

The mole fraction of hexane in the liquid phase is calculated as,

  Mole fraction of hexane=0.1740mole0.1740mole+0.1995mole

  Mole fraction of hexane=0.1740mole0.3735mole

  Mole fraction of hexane=0.4658

The mole fraction of heptane is calculated from the mole fraction of hexane.

  Mole fraction of heptane=1-0.4658

  Mole fraction of heptane=0.5342

The mole fraction of hexane is 0.4658.

The mole fraction of heptane is 0.5342.

(b)

Interpretation Introduction

Interpretation:

The vapor pressures of hexane and heptane above the solution have to be given.

Concept Introduction:

The equilibrium between a liquid and its vapor produces a characteristic vapor pressure for each substance that depends on the temperature.  The lowering of the vapor pressure is caused by a lesser ability of the solvent to evaporate, so equilibrium is reached with a smaller concentration of the solvent in the gas phase.  The vapor pressure of a solution is expressed using Raoult’s law:

  PsolvsolvPosolv

The vapor pressure of the solvent (Psolv) above a dilute solution is equal to the mole fraction of the solvent solv) times the vapor pressure of the pure solvent (Posolv).

(b)

Expert Solution
Check Mark

Answer to Problem 12.85QE

The vapor pressure of hexane is 129.5torr.

The vapor pressure of heptane is 49.3066torr.

Explanation of Solution

Given,

Weight of hexane        =15.0g

Weight of heptane        =20.0g

Vapor pressure of hexane    =278torr

Vapor pressure of heptane    =92.3torr

The moles of hexane are calculated from its molar mass.

  Moles of hexane=15g×1mol86.18g=0.1740mole

The mole fraction of hexane in the liquid phase is calculated as,

  Mole fraction of hexane=0.1740mole0.1740mole+0.1995mole

  Mole fraction of hexane=0.1740mole0.3735mole

  Mole fraction of hexane=0.4658

The vapor pressure of hexane is given as,

  Vapor pressure of hexane=χhexanePohexane

  Vapor pressure of hexane=0.4658×278torr

  Vapor pressure of hexane=129.5torr

The moles of heptane are calculated from its molar mass.

  Moles of heptane=20g×1mol100.21g=0.1995mole

The mole fraction of heptane is calculated from the mole fraction of hexane.

  Mole fraction of heptane=1-0.4658

  Mole fraction of heptane=0.5342

The vapor pressure of heptane is given as,

  Vapor pressure of heptane=χheptanePoheptane

  Vapor pressure of heptane=0.5342×92.3torr

  Vapor pressure of heptane=49.3066torr

The vapor pressure of hexane is 129.5torr.

The vapor pressure of heptane is 49.3066 torr.

(c)

Interpretation Introduction

Interpretation:

The mole fraction of heptane and hexane in vapor phase has to be given.

Concept Introduction:

Refer to part (a) and (b).

(c)

Expert Solution
Check Mark

Answer to Problem 12.85QE

The mole fraction of hexane in vapor pressure is 0.7242.

The mole fraction of heptane in vapor pressure is 0.2757.

Explanation of Solution

The vapor pressure of hexane 129.5torr.

The vapor pressure of heptane is 49.3066 torr.

The total vapor pressure is 178.80torr.

The mole fraction of hexane and hexane are calculated as,

  Mole fraction=Vaporpressureofheptane/hexane(intorr)Totalvaporpressure(intorr)

  Mole fraction of hexane=129.5torr178.80torr=0.7242

  Mole fraction of heptane=49.30torr178.80torr=0.2757

The mole fraction of hexane in vapor pressure is 0.7242.

The mole fraction of heptane in vapor pressure is 0.2757.

Want to see more full solutions like this?

Subscribe now to access step-by-step solutions to millions of textbook problems written by subject matter experts!

Chapter 12 Solutions

Chemistry: Principles and Practice

Ch. 12 - Prob. 12.11QECh. 12 - Prob. 12.12QECh. 12 - Create a flow diagram, similar to those used in...Ch. 12 - Prob. 12.14QECh. 12 - Prob. 12.15QECh. 12 - Prob. 12.16QECh. 12 - Prob. 12.17QECh. 12 - Prob. 12.18QECh. 12 - Prob. 12.19QECh. 12 - Prob. 12.20QECh. 12 - Prob. 12.21QECh. 12 - Prob. 12.22QECh. 12 - Prob. 12.23QECh. 12 - Prob. 12.24QECh. 12 - Prob. 12.25QECh. 12 - Prob. 12.26QECh. 12 - Prob. 12.27QECh. 12 - What is the molality of copper(II) bromide (CuBr2)...Ch. 12 - Prob. 12.29QECh. 12 - Prob. 12.30QECh. 12 - A water solution of sodium hypochlorite (NaOCl) is...Ch. 12 - Prob. 12.32QECh. 12 - Prob. 12.33QECh. 12 - Vinegar is a 5.0% solution of acetic acid...Ch. 12 - Prob. 12.35QECh. 12 - A 2.77 M NaOH solution in water has a density of...Ch. 12 - The density of a 3.75 M aqueous sulfuric acid...Ch. 12 - Prob. 12.40QECh. 12 - Prob. 12.41QECh. 12 - Prob. 12.42QECh. 12 - Predict the relative solubility of each compound...Ch. 12 - Predict the relative solubility of each compound...Ch. 12 - Prob. 12.45QECh. 12 - Prob. 12.46QECh. 12 - Prob. 12.47QECh. 12 - Prob. 12.48QECh. 12 - Prob. 12.49QECh. 12 - The solubility of ethylene (C2H4) in water at 20 C...Ch. 12 - Prob. 12.51QECh. 12 - Prob. 12.52QECh. 12 - Prob. 12.53QECh. 12 - Prob. 12.54QECh. 12 - Prob. 12.55QECh. 12 - Prob. 12.56QECh. 12 - From the data presented in Figure 12.11, determine...Ch. 12 - Prob. 12.58QECh. 12 - Prob. 12.59QECh. 12 - Prob. 12.60QECh. 12 - Prob. 12.61QECh. 12 - Prob. 12.62QECh. 12 - The vapor pressure of chloroform (CHCl3) is 360...Ch. 12 - Prob. 12.64QECh. 12 - Prob. 12.65QECh. 12 - Prob. 12.66QECh. 12 - Prob. 12.67QECh. 12 - Prob. 12.68QECh. 12 - Prob. 12.69QECh. 12 - Prob. 12.70QECh. 12 - A solution of 1.00 g of a protein in 20.0 mL water...Ch. 12 - Prob. 12.72QECh. 12 - Arrange the following aqueous solutions in order...Ch. 12 - Arrange the following solutions in order of...Ch. 12 - Prob. 12.75QECh. 12 - An aqueous solution of sodium bromide freezes at...Ch. 12 - Prob. 12.77QECh. 12 - Prob. 12.78QECh. 12 - Prob. 12.79QECh. 12 - Prob. 12.80QECh. 12 - A 0.029 M solution of potassium sulfate has an...Ch. 12 - The freezing point of a 0.031-m solution of...Ch. 12 - Prob. 12.83QECh. 12 - Prob. 12.84QECh. 12 - Prob. 12.85QECh. 12 - Prob. 12.86QECh. 12 - Prob. 12.87QECh. 12 - Prob. 12.88QECh. 12 - Prob. 12.89QECh. 12 - Prob. 12.90QECh. 12 - Predict the relative solubility of each compound...Ch. 12 - Prob. 12.92QECh. 12 - Prob. 12.94QECh. 12 - Prob. 12.95QECh. 12 - Prob. 12.96QECh. 12 - Sketch graphs of total vapor pressure versus the...Ch. 12 - Prob. 12.98QECh. 12 - Prob. 12.99QECh. 12 - Prob. 12.100QECh. 12 - Prob. 12.101QECh. 12 - Prob. 12.102QECh. 12 - Prob. 12.103QECh. 12 - A 10.00-mL sample of a 24.00% solution of ammonium...Ch. 12 - Prob. 12.105QECh. 12 - In the 1986 Lake Nyos disaster (see the chapter...Ch. 12 - Prob. 12.107QE
Knowledge Booster
Background pattern image
Chemistry
Learn more about
Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, chemistry and related others by exploring similar questions and additional content below.
Similar questions
Recommended textbooks for you
  • Text book image
    Chemistry: Principles and Practice
    Chemistry
    ISBN:9780534420123
    Author:Daniel L. Reger, Scott R. Goode, David W. Ball, Edward Mercer
    Publisher:Cengage Learning
    Text book image
    Chemistry & Chemical Reactivity
    Chemistry
    ISBN:9781337399074
    Author:John C. Kotz, Paul M. Treichel, John Townsend, David Treichel
    Publisher:Cengage Learning
    Text book image
    Chemistry & Chemical Reactivity
    Chemistry
    ISBN:9781133949640
    Author:John C. Kotz, Paul M. Treichel, John Townsend, David Treichel
    Publisher:Cengage Learning
  • Text book image
    Chemistry
    Chemistry
    ISBN:9781305957404
    Author:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste
    Publisher:Cengage Learning
    Text book image
    Chemistry: An Atoms First Approach
    Chemistry
    ISBN:9781305079243
    Author:Steven S. Zumdahl, Susan A. Zumdahl
    Publisher:Cengage Learning
    Text book image
    Chemistry
    Chemistry
    ISBN:9781133611097
    Author:Steven S. Zumdahl
    Publisher:Cengage Learning
Text book image
Chemistry: Principles and Practice
Chemistry
ISBN:9780534420123
Author:Daniel L. Reger, Scott R. Goode, David W. Ball, Edward Mercer
Publisher:Cengage Learning
Text book image
Chemistry & Chemical Reactivity
Chemistry
ISBN:9781337399074
Author:John C. Kotz, Paul M. Treichel, John Townsend, David Treichel
Publisher:Cengage Learning
Text book image
Chemistry & Chemical Reactivity
Chemistry
ISBN:9781133949640
Author:John C. Kotz, Paul M. Treichel, John Townsend, David Treichel
Publisher:Cengage Learning
Text book image
Chemistry
Chemistry
ISBN:9781305957404
Author:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste
Publisher:Cengage Learning
Text book image
Chemistry: An Atoms First Approach
Chemistry
ISBN:9781305079243
Author:Steven S. Zumdahl, Susan A. Zumdahl
Publisher:Cengage Learning
Text book image
Chemistry
Chemistry
ISBN:9781133611097
Author:Steven S. Zumdahl
Publisher:Cengage Learning
Solutions: Crash Course Chemistry #27; Author: Crash Course;https://www.youtube.com/watch?v=9h2f1Bjr0p4;License: Standard YouTube License, CC-BY