Concept explainers
Interpretation:
The
Concept introduction:
Bond enthalpy:
The measure of stability of molecule is bond enthalpy. The change in enthalpy is related in breaking a specific bond of 1 mole of gaseous molecule. In solids and liquids bond enthalpies are affected by neighboring molecules. There is possibility to predict the enthalpy of reaction using the average bond enthalpies. Energy is always needed for the breaking of
The enthalpy of reaction in gas phase is given by,
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General Chemistry - Standalone book (MindTap Course List)
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- Write 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_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_forwardCompare your answers from parts a and b of Exercise 69 of Chapter 3 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_forward
- Ethanol can be made by the reaction of ethylene and water: H2C=CH2(g) + H2O(g) CH3CH2OH(g) Use bond dissociation enthalpies to estimate the enthalpy change in this reaction. Compare the value obtained to the value calculated from enthalpies of formation.arrow_forwardWhich of these compounds would be expected to have the LARGEST lattice energy? Why? Li2O, Rb2O, or Na2O .arrow_forwardThe magnitude of the lattice energy (energy required to separate the ions) for the compounds K2O and CaO are shown below with respect to Coulombic attraction, which is the best explanation for the difference in lattice energy?arrow_forward
- Consider the following balanced reaction: 2 A2 + B → C + 2 D What is the enthalpy of reaction if the enthalpy of formation of the compounds is given as Compound Enthalpy of Formation (kJ/mol) A2 -16.43 B 15.34 C 10.21 D 17.75arrow_forwardA scientist studies the bond energies of different compounds containing nitrogen (N). The scientist observes that the N–N bonds in one group of compounds have a bond energy of 209 kJ/mol, while the N–N bonds in another group of compounds have a bond energy of 418 kJ/mol. In one or two sentences, postulate a reason for this difference.arrow_forwardUse average bond energies together with the standard enthalpy of formation of C( g) (718.4 kJ/mol) to estimate the standard enthalpy of formation of gaseous benzene, C6H6( g). (Remember that average bond energies apply to the gas phase only.) Compare the value you obtain using average bond energies to the actual standard enthalpy of formation of gaseous benzene,82.9 kJ/mol. What does the difference between these two values tell you about the stability of benzene?arrow_forward
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