Chemistry
12th Edition
ISBN: 9780078021510
Author: Raymond Chang Dr., Kenneth Goldsby Professor
Publisher: McGraw-Hill Education
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Textbook Question
Chapter 9.10, Problem 1RC
Why does ΔH°rxn calculated using bond enthalpies not always agree with that calculated using ΔH°f values?
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Students have asked these similar questions
Use the average bond enthalpies from Table 8.3 in your textbook to estimate ΔHΔH for the formation of CO2(g) by the following reaction:
CH4(g) + 2O2(g) --> CO2(g) +2H2O(g)
For the reaction:
2C₂H6(g) + 70₂(g) 4CO₂(g) + 6H₂O(g)
Part 1 of 2
Predict the enthalpy of reaction from the average bond enthalpies. Be sure your answer has the correct number of significant digits.
Note: Reference the Bond energies table for additional information.
ΔΗ
rxn
Part 2 of 2
-
kJ
mol
Calculate the enthalpy of reaction from the standard enthalpies of formation of the reactant and product molecules. Be sure your answer has
the correct number of significant digits.
Note: Reference the Thermodynamic properties of pure substances table for additional information.
AH =
rxn
kJ
mol
0XP
How does the bond energy of HCl(g) differ from the standard enthalpy of formation of HCl(g)?
Chapter 9 Solutions
Chemistry
Ch. 9.1 - Prob. 1RCCh. 9.2 - Use Lewis dot symbols to represent the formation...Ch. 9.2 - Use Lewis dot symbols to represent the formation...Ch. 9.3 - Which of the following compounds has a larger...Ch. 9.4 - Why is it not possible for hydrogen to form double...Ch. 9.5 - Which of the following bonds is covalent, which is...Ch. 9.5 - Identify the electrostatic potential maps shown...Ch. 9.6 - Write the Lewis structure for carbon disulfide...Ch. 9.6 - Write the Lewis structure for formic acid (HCOOH).Ch. 9.6 - Write the Lewis structure for the nitrite ion...
Ch. 9.6 - The molecular model shown here represents guanine,...Ch. 9.7 - Write formal charges for the nitrite ion (NO2).Ch. 9.7 - Draw the most reasonable Lewis structure of a...Ch. 9.7 - Consider three possible atomic arrangements for...Ch. 9.8 - Draw three resonance structures for the...Ch. 9.8 - The molecular model shown here represents...Ch. 9.9 - Prob. 9PECh. 9.9 - Prob. 10PECh. 9.9 - Prob. 11PECh. 9.9 - Write the Lewis structure of sulfur tetrafluoride...Ch. 9.9 - Both boron and aluminum tend to form compounds in...Ch. 9.10 - Calculate the enthalpy of the reaction...Ch. 9.10 - For the reaction H2(g)+C2H4(g)C2H6(g) (a) Estimate...Ch. 9.10 - Why does Hrxn calculated using bond enthalpies not...Ch. 9 - What is a Lewis dot symbol? To what elements does...Ch. 9 - Use the second member of each group from Group 1A...Ch. 9 - Prob. 9.3QPCh. 9 - Write Lewis dot symbols for the following ions:...Ch. 9 - Write Lewis dot symbols for the following atoms...Ch. 9 - Explain what an ionic bond is.Ch. 9 - Prob. 9.7QPCh. 9 - Name five metals and five nonmetals that are very...Ch. 9 - Name one ionic compound that contains only...Ch. 9 - Name one ionic compound that contains a polyatomic...Ch. 9 - Prob. 9.11QPCh. 9 - In which of the following states would NaCl be...Ch. 9 - Prob. 9.14QPCh. 9 - An ionic bond is formed between a cation A+ and an...Ch. 9 - Prob. 9.16QPCh. 9 - Use Lewis dot symbols to show the transfer of...Ch. 9 - Prob. 9.18QPCh. 9 - For each of the following pairs of elements, state...Ch. 9 - Prob. 9.20QPCh. 9 - What is lattice energy and what role does it play...Ch. 9 - Explain how the lattice energy of an ionic...Ch. 9 - Specify which compound in the following pairs of...Ch. 9 - Compare the stability (in the solid state) of the...Ch. 9 - Use the Born-Haber cycle outlined in Section 9.3...Ch. 9 - Calculate the lattice energy of calcium chloride...Ch. 9 - What is Lewiss contribution to our understanding...Ch. 9 - Use an example to illustrate each of the following...Ch. 9 - What is the difference between a Lewis dot symbol...Ch. 9 - How many lone pairs are on the underlined atoms in...Ch. 9 - Compare single, double, and triple bonds in a...Ch. 9 - Compare the properties of ionic compounds and...Ch. 9 - Define electronegativity, and explain the...Ch. 9 - List the following bonds in order of increasing...Ch. 9 - Arrange the following bonds in order of increasing...Ch. 9 - Four atoms are arbitrarily labeled D, E, F, and G....Ch. 9 - List the following bonds in order of increasing...Ch. 9 - Classify the following bonds as ionic, polar...Ch. 9 - Classify the following bonds as ionic, polar...Ch. 9 - Prob. 9.41QPCh. 9 - 9.42 Explain the concept of formal change. Do...Ch. 9 - Write Lewis structures for the following molecules...Ch. 9 - Write Lewis structures for the following molecules...Ch. 9 - Write Lewis structures for the following...Ch. 9 - Write Lewis structures for the following...Ch. 9 - The following Lewis structures for (a) HCN, (b)...Ch. 9 - The skeletal structure of acetic acid shown here...Ch. 9 - Define bond length, resonance, and resonance...Ch. 9 - Is it possible to trap a resonance structure of a...Ch. 9 - Write Lewis structures for the following species,...Ch. 9 - Draw three resonance structures for the chlorate...Ch. 9 - Write three resonance structures for hydrazoic...Ch. 9 - Draw two resonance structures for diazomethane,...Ch. 9 - Draw three resonance structures for the molecule...Ch. 9 - Draw three reasonable resonance structures for the...Ch. 9 - Why does the octet rule not hold for many...Ch. 9 - Give three examples of compounds that do not...Ch. 9 - Because fluorine has seven valence electrons...Ch. 9 - What is a coordinate covalent bond? Is it...Ch. 9 - Prob. 9.61QPCh. 9 - In the vapor phase, beryllium chloride consists of...Ch. 9 - Of the noble gases, only Kr, Xe, and Rn are known...Ch. 9 - Write a Lewis structure for SbCl5. Does this...Ch. 9 - Prob. 9.65QPCh. 9 - Write Lewis structures for the reaction...Ch. 9 - What is bond enthalpy? Bond enthalpies of...Ch. 9 - Explain why the bond enthalpy of a molecule is...Ch. 9 - From the following data, calculate the average...Ch. 9 - For the reaction O(g)+O2(g)O3(g)H=107.2kJ/mol...Ch. 9 - The bond enthalpy of F2(g) is 156.9 kJ/mol....Ch. 9 - For the reaction 2C2H6(g)+7O2(g)4CO2(g)+6H2O(g)...Ch. 9 - Prob. 9.73QPCh. 9 - Which of the following are ionic compounds? Which...Ch. 9 - Prob. 9.75QPCh. 9 - Use ionization energy (see Table 8.2) and electron...Ch. 9 - Prob. 9.78QPCh. 9 - Prob. 9.79QPCh. 9 - Write three reasonable resonance structures for...Ch. 9 - Prob. 9.81QPCh. 9 - Give an example of an ion or molecule containing...Ch. 9 - Draw four reasonable resonance structures for the...Ch. 9 - Prob. 9.84QPCh. 9 - Draw reasonable resonance structures for the...Ch. 9 - Are the following statements true or false? (a)...Ch. 9 - Prob. 9.87QPCh. 9 - Using the following information and the fact that...Ch. 9 - Prob. 9.89QPCh. 9 - Which of the following molecules has the shortest...Ch. 9 - Most organic acids can be represented as RCOOH,...Ch. 9 - Which of the following species are isoelectronic:...Ch. 9 - The following species have been detected in...Ch. 9 - The amide ion, NH2, is a Brnsted base. Represent...Ch. 9 - Draw Lewis structures for the following organic...Ch. 9 - The triiodide ion (I3) in which the I atoms are...Ch. 9 - Compare the bond enthalpy of F2 with the energy...Ch. 9 - Methyl isocyanate (CH3NCO) is used to make certain...Ch. 9 - Prob. 9.99QPCh. 9 - Prob. 9.100QPCh. 9 - Prob. 9.101QPCh. 9 - Draw Lewis structures for the following...Ch. 9 - Prob. 9.103QPCh. 9 - Prob. 9.104QPCh. 9 - Draw Lewis structures for the following organic...Ch. 9 - Write Lewis structures for the following four...Ch. 9 - Prob. 9.107QPCh. 9 - Prob. 9.108QPCh. 9 - Write three resonance structures for (a) the...Ch. 9 - (a) From the following data calculate the bond...Ch. 9 - Prob. 9.111QPCh. 9 - What are the other two reasons for choosing (b) in...Ch. 9 - Prob. 9.113QPCh. 9 - The NO bond distance in nitric oxide is 115 pm,...Ch. 9 - Prob. 9.115QPCh. 9 - Prob. 9.116QPCh. 9 - Prob. 9.117QPCh. 9 - Prob. 9.118QPCh. 9 - Draw a Lewis structure for nitrogen pentoxide...Ch. 9 - In the gas phase, aluminum chloride exists as a...Ch. 9 - The hydroxyl radical (OH) plays an important role...Ch. 9 - Experiments show that it takes 1656 kJ/mol to...Ch. 9 - Calculate Hrxn at 25C of the reaction between...Ch. 9 - Calculate Hrxn at 25C of the reaction between...Ch. 9 - Draw three resonance structures of sulfur dioxide...Ch. 9 - Vinyl chloride (C2H3Cl) differs from ethylene...Ch. 9 - Prob. 9.127QPCh. 9 - The American chemist Robert S. Mulliken suggested...Ch. 9 - Prob. 9.129QPCh. 9 - A student in your class claims that magnesium...Ch. 9 - Shown here is a skeletal structure of borazine...Ch. 9 - Calculate the wavelength of light needed to carry...Ch. 9 - Prob. 9.133QPCh. 9 - From the lattice energy of KCl in Table 9.1 and...Ch. 9 - The species H3+ is the simplest polyatomic ion....Ch. 9 - The bond enthalpy of the CN bond in the amide...Ch. 9 - In 1999 an unusual cation containing only nitrogen...Ch. 9 - Nitroglycerin, one of the most commonly used...Ch. 9 - Give a brief description of the medical uses of...Ch. 9 - Prob. 9.140QPCh. 9 - The isolated O2 ion is unstable so it is not...Ch. 9 - When irradiated with light of wavelength 471.7 nm,...Ch. 9 - Recall from Chapter 8 that the product of the...Ch. 9 - The reaction between fluorine (F2) with ethane...Ch. 9 - A new allotrope of oxygen, O4, has been reported....Ch. 9 - Because bond formation is exothermic, when two...Ch. 9 - Estimate Hf for sodium astatide (NaAt) according...
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