   # The enthalpy of vaporization of ethanol is 38.7 kJ/mol at its boiling point (78°C). Determine ∆ S sys , ∆ S surr , and ∆ S univ when 1.00 mole of ethanol is vaporized at 78°C and 1.00 atm. ### Chemistry: An Atoms First Approach

2nd Edition
Steven S. Zumdahl + 1 other
Publisher: Cengage Learning
ISBN: 9781305079243

#### Solutions

Chapter
Section ### Chemistry: An Atoms First Approach

2nd Edition
Steven S. Zumdahl + 1 other
Publisher: Cengage Learning
ISBN: 9781305079243
Chapter 16, Problem 40E
Textbook Problem
66 views

## The enthalpy of vaporization of ethanol is 38.7 kJ/mol at its boiling point (78°C). Determine ∆Ssys, ∆Ssurr, and ∆Suniv when 1.00 mole of ethanol is vaporized at 78°C and 1.00 atm.

Interpretation Introduction

Interpretation: The enthalpy of vaporization, boiling point, number of moles and pressure of Ethanol is given. The value of ΔSsys,ΔSsurr and ΔSuniv is to be calculated.

Concept introduction: Entropy is the measure of degree of disorder or randomness. The value of ΔS is calculated using the formula,

ΔS=ΔHT

### Explanation of Solution

Given

Boiling point of Ethanol is 78°C .

Enthalpy of vaporization of Ethanol is 38.7kJ/mol .

The conversion of kilo-joule (kJ) into joule (J) is done as,

1kJ=103J

Hence,

The conversion of 38.7kJ into joule is,

38.7kJ=(38.7×103)J=38700J

The conversion of degree Celsius (°C) into Kelvin (K) is done as,

T(K)=T(°C)+273

Hence,

The conversion of 78°C into Kelvin is,

T(K)=T(°C)+273T(K)=(78+273)K=351K

Formula

The value of ΔSsys is calculated using the formula,

ΔSsys=ΔHT

Where,

• ΔH is the enthalpy of vaporization.
• T is the boiling point.
• ΔSsys is the entropy of system.

Substitute the values of ΔHfusion and ΔSfusion in the above equation.

ΔSsys=ΔHT=38700J351K=110.26J/K_

Given

Boiling point of Ethanol is 78°C .

Enthalpy of vaporization of Ethanol is 38.7kJ/mol .

The conversion of kilo-joule (kJ) into joule (J) is done as,

1kJ=103J

Hence,

The conversion of 38.7kJ into joule is,

38.7kJ=(38

### Still sussing out bartleby?

Check out a sample textbook solution.

See a sample solution

#### The Solution to Your Study Problems

Bartleby provides explanations to thousands of textbook problems written by our experts, many with advanced degrees!

Get Started

Find more solutions based on key concepts
Insufficient dietary protein can cause slowed protein synthesis. hepatitis. accelerated growth in children. all...

Nutrition: Concepts and Controversies - Standalone book (MindTap Course List)

The senses cannot be completely relied on. Why?

An Introduction to Physical Science

In what way has biotechnology had an impact on agriculture in the United States?

Human Heredity: Principles and Issues (MindTap Course List)

Review. The system shown in Figure P8.6 consists of a light, inextensible cord, light, frictionless pulleys, an...

Physics for Scientists and Engineers, Technology Update (No access codes included)

Which distribution pattern is the rarest?

Oceanography: An Invitation To Marine Science, Loose-leaf Versin 