Concept explainers
Use bond enthalpies to determine
Want to see the full answer?
Check out a sample textbook solutionChapter 8 Solutions
Chemistry - With Access (Looseleaf) (Custom)
- In general the higher the charge on the ions in an ionic compound, the more favorable the lattice energy. Why do some stable ionic compounds have +1 charged ions even though +4, + 5, and +6 charged ions would have a more favorable lattice energy?arrow_forwardCompare your answers from parts a and b of Exercise 69 with H values calculated for each reaction using standard enthalpies of formation in Appendix 4. Do enthalpy changes calculated from bond energies give a reasonable estimate of the actual values?arrow_forwardWhen a reaction is exothermic, is the sum of bond energies of products or of reactants greater?arrow_forward
- Dinitrogen monoxide, N2O, can decompose to nitrogen and oxygen gas: 2 N2O(g) 2 N2(g) + O2(g) Use bond dissociation enthalpies to estimate the enthalpy change for this reaction.arrow_forwardUsing the bond energies in Table 7.2, determine the approximate enthalpy change for each of the following reactions: (a) Cl2(g)+3F2(g)2ClF3(g) (b) H2C=CH2(g)+H2(g)H3CCH3(g) (c) 2C2H6(g)+7O2(g)4CO2(g)+6H2O(g) .arrow_forwardBond Enthalpy When atoms of the hypothetical element X are placed together, they rapidly undergo reaction to form the X2 molecule: X(g)+X(g)X2(g) a Would you predict that this reaction is exothermic or endothermic? Explain. b Is the bond enthalpy of X2 a positive or a negative quantity? Why? c Suppose H for the reaction is 500 kJ/mol. Estimate the bond enthalpy of the X2 molecule. d Another hypothetical molecular compound, Y2(g), has a bond enthalpy of 750 kJ/mol, and the molecular compound XY(g) has a bond enthalpy of 1500 kJ/mol. Using bond enthalpy information, calculate H for the following reaction. X2(g)+Y2(g)2XY(g) e Given the following information, as well as the information previously presented, predict whether or not the hypothetical ionic compound AX is likely to form. In this compound, A forms the A+ cation, and X forms the X anion. Be sure to justify your answer. Reaction: A(g)+12X2(g)AX(s)The first ionization energy of A(g) is 400 kJ/mol. The electron affinity of X(g) is 525 kJ/mol. The lattice energy of AX(s) is 100 kJ/mol. f If you predicted that no ionic compound would form from the reaction in Part e, what minimum amount of AX(s) lattice energy might lead to compound formation?arrow_forward
- hat is the enthalpy change for a process? Is enthalpy a state function? In what experimental apparatus are enthalpy changes measured?arrow_forwardDraw a curve that describes the energy of a system with H and Cl atoms at varying distances. Then, find the minimum energy of this curve two ways. (a) Use the bond energy found in Table 8.1 to calculate the energy for one single HCl bond (Hint: How many bonds are in a mole?) (b) Use the enthalpy of reaction and the bond energies for H2 and Cl2 to solve for the energy of one mole of HCl bonds. H2(g)+Cl2(g)2HCl(g)Hrxn=184.7kJ/molarrow_forwardWrite all resonance structures of chlorobenzene, C6H5Cl, a molecule with the same cyclic structure as benzene. In all structures, keep the CCl bond as a single bond. Which resonance structures are the most important?arrow_forward
- Using the bond dissociation enthalpies in Table 8.8, estimate the enthalpy of combustion of gaseous methane, CH4, to give water vapor and carbon dioxide gas.arrow_forwardHydrogenation reactions, which involve the addition of H2 to a molecule, are widely used in industry to transform one compound into another. For example, 1-butene (C4H8) is converted to butane (C4H10) by addition of H2. Use the bond dissociation enthalpies in Table 8.8 to estimate the enthalpy change for this hydrogenation reaction.arrow_forwardWhich statement(s) is/are true about bond enthalpy? (a) The bond energy for a triple bond between A and B is three times that of a single bond between A and B. (b) H for the breaking of a bond is always a negative number. (c) Energy is required to make a bond. (d) Bond enthalpy is defined only for bonds broken or formed in the gaseous state. (e) The presence of bonds does not influence the geometry of a molecule. However, the presence of bonds affects the value of the bond enthalpy between two atoms.arrow_forward
- General Chemistry - Standalone book (MindTap Cour...ChemistryISBN:9781305580343Author:Steven D. Gammon, Ebbing, Darrell Ebbing, Steven D., Darrell; Gammon, Darrell Ebbing; Steven D. Gammon, Darrell D.; Gammon, Ebbing; Steven D. Gammon; DarrellPublisher:Cengage LearningChemistry & Chemical ReactivityChemistryISBN:9781337399074Author:John C. Kotz, Paul M. Treichel, John Townsend, David TreichelPublisher:Cengage LearningChemistry: Principles and PracticeChemistryISBN:9780534420123Author:Daniel L. Reger, Scott R. Goode, David W. Ball, Edward MercerPublisher:Cengage Learning
- Chemistry by OpenStax (2015-05-04)ChemistryISBN:9781938168390Author:Klaus Theopold, Richard H Langley, Paul Flowers, William R. Robinson, Mark BlaserPublisher:OpenStaxChemistry & Chemical ReactivityChemistryISBN:9781133949640Author:John C. Kotz, Paul M. Treichel, John Townsend, David TreichelPublisher:Cengage LearningChemistryChemistryISBN:9781305957404Author:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCostePublisher:Cengage Learning