N Average Bond Enthalpies (kJ/mol) Single Bonds C-H 413 C-C 348 H-O 463 N-H 391 N-N 163 N-O 201 N-F 272 N-CI 200 N-Br 243 155 O-o 146 060 F 190 N 293 N-O Cl-F 253 a-a 242 C-o 358 485 C-a 328 C-Br 276 240 1- 0-a 203 0- 234 Br-F 237 Br-Ci 218 Br-Br 193 H-S S-F 327 S-CI 253 S-Br 218 259 9 334 H-F 567 H-CI 431 H-Br 366 -a 208 1-Br 175 151 1-1 Si-H 323 Si-Si 226 Si-C 301 Si-O 368 S-S 926 I-H Multiple Bonds 495 N-N 418 N N 941 IO 614 C C 839 C-N 615 C N 891 C-o 799 C O 1072 S-o 623 S-S 418 101 Using the bond enthalpies found on the next page, approximate the AHpxn for the following reaction: но Но CH3 H3C CH2 о'н H3C A. -19.8 kJ/mol B. 25.1 kJ/mol C. -31.7 kJ/mol *84 D. 38.5 kJ/mol E. -42.0 kJ/mol 1-0

N Average Bond Enthalpies (kJ/mol) Single Bonds C-H 413 C-C 348 H-O 463 N-H 391 N-N 163 N-O 201 N-F 272 N-CI 200 N-Br 243 155 O-o 146 060 F 190 N 293 N-O Cl-F 253 a-a 242 C-o 358 485 C-a 328 C-Br 276 240 1- 0-a 203 0- 234 Br-F 237 Br-Ci 218 Br-Br 193 H-S S-F 327 S-CI 253 S-Br 218 259 9 334 H-F 567 H-CI 431 H-Br 366 -a 208 1-Br 175 151 1-1 Si-H 323 Si-Si 226 Si-C 301 Si-O 368 S-S 926 I-H Multiple Bonds 495 N-N 418 N N 941 IO 614 C C 839 C-N 615 C N 891 C-o 799 C O 1072 S-o 623 S-S 418 101 Using the bond enthalpies found on the next page, approximate the AHpxn for the following reaction: но Но CH3 H3C CH2 о'н H3C A. -19.8 kJ/mol B. 25.1 kJ/mol C. -31.7 kJ/mol *84 D. 38.5 kJ/mol E. -42.0 kJ/mol 1-0

Chemistry for Engineering Students

4th Edition

ISBN:9781337398909

Author:Lawrence S. Brown, Tom Holme

Publisher:Lawrence S. Brown, Tom Holme

Chapter9: Energy And Chemistry

Section: Chapter Questions

Problem 9.77PAE: 9.77 When a reaction is exothermic, is the sum of bond energies of products or of reactants greater?

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9.77 When a reaction is exothermic, is the sum of bond energies of products or of reactants greater?
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