Use the bond enthalpies given to estimate the heat released when ethene,CH₂=CH₂,reacts with HBr to give CH₃CH₂Br.Bond enthalpies (kJ.mol^-¹): C-H,412; C-C,348; C=C,612; C-Br,276; Br-Br,193; H-Br,366.

Question

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The reaction involves breaking a C=C bond (612 kJ/mol) and an H-Br bond (366 kJ/mol), and forming a C-C bond (348 kJ/mol), a C-H bond (412 kJ/mol), and a C-Br bond (276 kJ/mol). The heat released is calculated as the difference between the total energy of bonds broken and formed: (612 + 366) - (348 + 412 + 276) = 58 kJ/mol.

Use the Bond Enthalpies Given to Estimate the Heat Released