Chemistry
Chemistry
4th Edition
ISBN: 9780078021527
Author: Julia Burdge
Publisher: McGraw-Hill Education
bartleby

Videos

Question
Book Icon
Chapter 5, Problem 93AP
Interpretation Introduction

Interpretation:

Whether the standard enthalpy of the reaction is equal to the standard enthalpy of formation or not is to be determined.

Concept introduction:

The standard enthalpy of a reaction is the amount of enthalpy to occur under standard conditions.

The standard enthalpy of a reaction can be determined using the equation given below:

ΔH°rxn=nΔHf°(products)mΔHf°(reactants)

Here, the stoichiometric coefficients are represented by m for the reactants and by n for the products, while the enthalpy of formation under standard conditions is represented by ΔHf°.

The value of enthalpy of the formation of an element is zero at its most stable state.

Expert Solution & Answer
Check Mark

Answer to Problem 93AP

Solution:

(a) ΔH°rxn=ΔH°f

(b) ΔH°rxn=ΔH°f

(c) ΔH°rxn=ΔH°f

(d) ΔH°rxn=ΔH°f

Explanation of Solution

a) H2(g)+S(rhombic)H2S(g)

The reaction is given as follows:

H2(g)+S(rhombic)H2S(g)

Hydrogen in its H2(g) form and sulfur in its rhombic form are the standard or most stable states of hydrogen (diatomic) and sulfur (transition state). So, their enthalpy of formation is zero, due to which the enthalpy of the reaction becomes the enthalpy of formation for H2S(g).

For the given equation, the enthalpy of the reaction is as follows:

ΔH°rxn=[ΔH°f(H2S(g))][ΔH°f(H2(g))+ΔH°f(S(rhombic))]

The enthalpy of formation is zero for H2(g) and S(rhombic).

Hence, for the reaction H2(g)+S(rhombic)H2S(g), the value of ΔH°rxn=ΔH°f[H2S(g)].

b) C(diamond)+O2(g)CO2(g)

The reaction is given as follows:

C(diamond)+O2(g)CO2(g)

Oxygen in its O2(g) form is the standard (diatomic) or most stable state of oxygen. So, its enthalpy of formation is zero. However, carbon is in its diamond form, and, for carbon, the most stable form is graphite, due to which its enthalpy of formation is not zero. Thus, the enthalpy of the reaction is not equal to the enthalpy of formation of CO2(g).

For the given equation, the enthalpy of the reaction is as follows:

ΔH°rxn=[ΔH°f(CO2(g))][ΔH°f(O2(g))+ΔH°f(C(diamond))]

The enthalpy of formation is zero for O2(g), but nonzero for C(diamond).

Hence, for the reaction C(diamond)+O2(g)CO2(g), the value of ΔH°rxn=ΔH°f[CO2(g)].

c) H2(g)+CuO(g)H2O(l)+Cu(s)

The reaction is given as follows:

H2(g)+CuO(g)H2O(l)+Cu(s)

Hydrogen in its H2(g) form is the standard (diatomic) or most stable state of hydrogen. So, its enthalpy of formation is zero. However, we have the formation of liquid as well in the by-products of the reaction, which has a nonzero enthalpy of formation. Thus, the enthalpy of the reaction is not equal to the enthalpy of formation of Cu(s).

For the given equation, the enthalpy of the reaction is as follows:

ΔH°rxn=[ΔH°f(H2O(l))+ΔH°f(Cu(s))][ΔH°f(H2(g))+ΔH°f(CuO(g))]

The enthalpy of formation is zero for H2(g), but nonzero for H2O(l).

Hence, for the reaction H2(g)+CuO(g)H2O(l)+Cu(s), the value of ΔH°rxn=ΔH°f[Cu(s)].

d) O(g)+O2(g)O3(g)

The reaction is given as follows:

O(g)+O2(g)O3(g)

Oxygen is in its diatomic form, that is, O2(g) form, which is the standard or most stable state of oxygen. So, its enthalpy of formation is zero. However, monoatomic oxygen is not the most stable form, due to which its enthalpy of formation is nonzero. Thus, the enthalpy of the reaction is not equal to the enthalpy of formation of O3(g).

For the given equation, the enthalpy of the reaction is as follows:

ΔH°rxn=[ΔH°f(O3(g))][ΔH°f(O2(g))+ΔH°f(O(g))]

The enthalpy of formation is zero for O2(g), but nonzero for O(g).

Hence, for the reaction O(g)+O2(g)O3(g), the value of ΔH°rxn=ΔH°f[O3(g)].

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 5 Solutions

Chemistry

Ch. 5.2 - Practice ProblemBUILD Calculate the magnitude of q...Ch. 5.2 - Prob. 1PPCCh. 5.2 - Calculate the overall change in internal energy...Ch. 5.2 - Calculate w, and determine whether work is done by...Ch. 5.2 - Prob. 3CPCh. 5.2 - Prob. 4CPCh. 5.3 - Prob. 1PPACh. 5.3 - Prob. 1PPBCh. 5.3 - Prob. 1PPCCh. 5.3 - Given the thermochemical equation: H 2 ( g ) + Br...Ch. 5.3 - Given the thermochemical equation: 2Cu 2 O ( s ) →...Ch. 5.4 - Prob. 1PPACh. 5.4 - Prob. 1PPBCh. 5.4 - Prob. 1PPCCh. 5.4 - Prob. 1CPCh. 5.4 - Prob. 2CPCh. 5.4 - Prob. 3CPCh. 5.4 - 5.4.4 Quantities of 50.0 mL of 1.00 M HCl and 50.0...Ch. 5.5 - Prob. 1PPACh. 5.5 - Prob. 1PPBCh. 5.5 - Prob. 1PPCCh. 5.5 - Prob. 1CPCh. 5.5 - Prob. 2CPCh. 5.5 - 5.5.3 Each diagram shows a systems before and...Ch. 5.5 - Prob. 4CPCh. 5.6 - Prob. 1PPACh. 5.6 - Prob. 1PPBCh. 5.6 - Prob. 1PPCCh. 5.6 - Prob. 1CPCh. 5.6 - Prob. 2CPCh. 5.6 - Prob. 3CPCh. 5.6 - Prob. 4CPCh. 5.7 - Prob. 1PPACh. 5.7 - Prob. 1PPBCh. 5.7 - Prob. 1PPCCh. 5.8 - Prob. 1PPACh. 5.8 - Prob. 1PPBCh. 5.8 - Practice ProblemCONCEPTUALIZE The diagrams...Ch. 5.9 - Practice ProblemATTEMPT Use the following data to...Ch. 5.9 - Prob. 1PPBCh. 5.9 - Prob. 1PPCCh. 5 - Using data from Appendix 2, calculate the standard...Ch. 5 - Prob. 2KSPCh. 5 - Prob. 3KSPCh. 5 - Using only whole-number coefficients, the...Ch. 5 - Prob. 1QPCh. 5 - Prob. 2QPCh. 5 - Prob. 3QPCh. 5 - 5.4 A truck initially trawling at 60 km/h is...Ch. 5 - These are various forms of energy: chemical, heat,...Ch. 5 - 5.6 Define these terms: thermochemistry,...Ch. 5 - 5.7 Stoichiometry is based on the law of...Ch. 5 - Prob. 8QPCh. 5 - Decomposition reactions are usually endothermic,...Ch. 5 - Prob. 10QPCh. 5 - Prob. 11QPCh. 5 - Prob. 12QPCh. 5 - Prob. 13QPCh. 5 - Prob. 14QPCh. 5 - Prob. 15QPCh. 5 - Prob. 16QPCh. 5 - Prob. 17QPCh. 5 - Use the following diagrams for Problems 5.17 and...Ch. 5 - Consider these changes. (a) Hg ( t ) → Hg ( g )...Ch. 5 - Prob. 20QPCh. 5 - Prob. 21QPCh. 5 - 5.22 Explain the meaning of this thermochemical...Ch. 5 - Consider this reaction: 2 CH 3 OH ( l ) + 3 O 2 (...Ch. 5 - Prob. 24QPCh. 5 - Prob. 25QPCh. 5 - Prob. 26QPCh. 5 - Prob. 27QPCh. 5 - Prob. 28QPCh. 5 - Prob. 29QPCh. 5 - Prob. 30QPCh. 5 - Prob. 31QPCh. 5 - For most biological processes, the changes in...Ch. 5 - Prob. 33QPCh. 5 - 5.34 Define calorimetry and describe two commonly...Ch. 5 - A 6.22-kg piece of copper metal is heated from 20...Ch. 5 - Prob. 36QPCh. 5 - Prob. 37QPCh. 5 - A 0.1375-g sample of solid magnesium is burned in...Ch. 5 - A quantity of 2 .00 × 10 2 mL of 0 .862 M HCl is...Ch. 5 - 5.40 A 50.75 g sample of water at is added to a...Ch. 5 - A 25.95-g sample of methanol at 35 .6°C is added...Ch. 5 - Prob. 42QPCh. 5 - Prob. 43QPCh. 5 - Consider the following data: Metal Al Cu Mass(g)...Ch. 5 - Prob. 45QPCh. 5 - Prob. 46QPCh. 5 - Prob. 47QPCh. 5 - Prob. 48QPCh. 5 - Prob. 49QPCh. 5 - Prob. 50QPCh. 5 - Prob. 51QPCh. 5 - Prob. 52QPCh. 5 - Prob. 53QPCh. 5 - Prob. 54QPCh. 5 - 5.55 Each diagram shows a system before and after...Ch. 5 - Prob. 56QPCh. 5 - 5.57 Determine the value of for the following...Ch. 5 - Prob. 58QPCh. 5 - Prob. 59QPCh. 5 - Prob. 60QPCh. 5 - Prob. 61QPCh. 5 - Prob. 62QPCh. 5 - Prob. 63QPCh. 5 - Prob. 64QPCh. 5 - Prob. 65QPCh. 5 - Prob. 66QPCh. 5 - Prob. 67QPCh. 5 - Prob. 68QPCh. 5 - Prob. 69QPCh. 5 - Prob. 70QPCh. 5 - Prob. 71QPCh. 5 - Prob. 72QPCh. 5 - Prob. 73QPCh. 5 - Prob. 74QPCh. 5 - Pentaborane - 9 ( B 5 H 9 ) is a colorless, highly...Ch. 5 - Prob. 76QPCh. 5 - Prob. 77QPCh. 5 - Prob. 78QPCh. 5 - Prob. 79QPCh. 5 - Prob. 80QPCh. 5 - Prob. 81APCh. 5 - Prob. 82APCh. 5 - Prob. 83APCh. 5 - Prob. 84APCh. 5 - Prob. 85APCh. 5 - Prob. 86APCh. 5 - Prob. 87APCh. 5 - Prob. 88APCh. 5 - Ethanol ( C 2 H 5 OH ) and gasoline (assumed to be...Ch. 5 - Prob. 90APCh. 5 - The heat of vaporization of a liquid ( Δ H vap )...Ch. 5 - Prob. 92APCh. 5 - Prob. 93APCh. 5 - Prob. 94APCh. 5 - Prob. 95APCh. 5 - Prob. 96APCh. 5 - 5.97 The enthalpy of combustion of benzoic add is...Ch. 5 - 5.98 At , the standard enthalpy of formation of...Ch. 5 - From the enthalpy of formation for CO, and the...Ch. 5 - In the nineteenth century, two scientists named...Ch. 5 - Prob. 101APCh. 5 - Prob. 102APCh. 5 - Prob. 103APCh. 5 - A quantity of 85 .0 mL of 0 .600 M HCl is mixed...Ch. 5 - Prob. 105APCh. 5 - Prob. 106APCh. 5 - A 4.117-g impure sample of glucose (C 4 H 12 O 6 )...Ch. 5 - Prob. 108APCh. 5 - In a constant-pressure calorimetry experiment, a...Ch. 5 - Prob. 110APCh. 5 - Give an example for each of the following...Ch. 5 - Prob. 112APCh. 5 - Prob. 113APCh. 5 - 5.114 A 3.52-g sample of ammonium nitrate was...Ch. 5 - 5.115 A quantity of is mixed with in a...Ch. 5 - Prob. 116APCh. 5 - Prob. 117APCh. 5 - Prob. 118APCh. 5 - Prob. 119APCh. 5 - Prob. 120APCh. 5 - 5.121 A gas company in Massachusetts charges 27...Ch. 5 - Prob. 122APCh. 5 - For reactions in condensed phases ( liquids and...Ch. 5 - Prob. 124APCh. 5 - Prob. 125APCh. 5 - The so-called hydrogen economy is based on...Ch. 5 - Prob. 127APCh. 5 - 5.128 Calculate the standard enthalpy change for...Ch. 5 - Prob. 129APCh. 5 - Prob. 130APCh. 5 - Why are cold, damp air and hot, humid air more...Ch. 5 - A woman expends 95 kJ of energy walking a...Ch. 5 - The carbon dioxide exhaled by sailors in a...Ch. 5 - Prob. 134APCh. 5 - Acetylene ( C 2 H 2 ) can be made by combining...Ch. 5 - (a) A person drinks four glasses of cold water ( 3...Ch. 5 - Both glucose and fructose are simple sugars with...Ch. 5 - Prob. 138APCh. 5 - Prob. 139APCh. 5 - Prob. 140APCh. 5 - Prob. 141APCh. 5 - Prob. 142APCh. 5 - 5.143 Hydrazine decomposes to form ammonia and...Ch. 5 - Prob. 144APCh. 5 - Prob. 145APCh. 5 - Prob. 1SEPPCh. 5 - What is the heat capacity ( C v ) of the...Ch. 5 - What is the energy content of the food? a) 22 .8...Ch. 5 - 4. What would be the effect on the result if the...
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
SEE MORE 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
    Physical Chemistry
    Chemistry
    ISBN:9781133958437
    Author:Ball, David W. (david Warren), BAER, Tomas
    Publisher:Wadsworth Cengage Learning,
  • Text book image
    Chemistry for Engineering Students
    Chemistry
    ISBN:9781337398909
    Author:Lawrence S. Brown, Tom Holme
    Publisher:Cengage Learning
    Text book image
    General Chemistry - Standalone book (MindTap Cour...
    Chemistry
    ISBN:9781305580343
    Author:Steven D. Gammon, Ebbing, Darrell Ebbing, Steven D., Darrell; Gammon, Darrell Ebbing; Steven D. Gammon, Darrell D.; Gammon, Ebbing; Steven D. Gammon; Darrell
    Publisher:Cengage Learning
    Text book image
    World of Chemistry
    Chemistry
    ISBN:9780618562763
    Author:Steven S. Zumdahl
    Publisher:Houghton Mifflin College Div
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
Physical Chemistry
Chemistry
ISBN:9781133958437
Author:Ball, David W. (david Warren), BAER, Tomas
Publisher:Wadsworth Cengage Learning,
Text book image
Chemistry for Engineering Students
Chemistry
ISBN:9781337398909
Author:Lawrence S. Brown, Tom Holme
Publisher:Cengage Learning
Text book image
General Chemistry - Standalone book (MindTap Cour...
Chemistry
ISBN:9781305580343
Author:Steven D. Gammon, Ebbing, Darrell Ebbing, Steven D., Darrell; Gammon, Darrell Ebbing; Steven D. Gammon, Darrell D.; Gammon, Ebbing; Steven D. Gammon; Darrell
Publisher:Cengage Learning
Text book image
World of Chemistry
Chemistry
ISBN:9780618562763
Author:Steven S. Zumdahl
Publisher:Houghton Mifflin College Div
The Laws of Thermodynamics, Entropy, and Gibbs Free Energy; Author: Professor Dave Explains;https://www.youtube.com/watch?v=8N1BxHgsoOw;License: Standard YouTube License, CC-BY