Question

Sports trainers treat sprains and soreness with ethyl bromide. it is manufactured by reacting ethylene with hydrogen bromide: h5sil9512 use bond energies to find the enthalpy change for this reaction

Answer 1

Answer:

-59 kJ/mol

Explanation:

If you read the question, you will see that  the requirement is missing. By Googling  the question, the complete content could  be found here: https://www.chegg.com/homework-help/sports-trainers-treat-sprains-soreness-ethyl-bromide-manufac-chapter-9-problem-51p-solution-9780077396671-exc

Change in Enthalpy for the reaction = summation of enthalpies of the bonds broken in the reactants - summation of enthalpies of the bonds formed in the product.

Reactants:

4 C-H bonds = 4*enthalpy of C-H bond = 4*413 kJ/mol = 1652 kJ/mol

1 C=C bond = 614 kJ/mol

1 H-Br bond = 363 kJ/mol

Summation of enthalpies of the bonds broken in the reactants = 1652 + 614 + 363 = 2629 kJ/mol

Product:

5 C-H bonds = 5*enthalpy of C-H bond = 5*413 kJ/mol = 2065 kJ/mol

1 C-C bond = 347 kJ/mol

1 C-Br bond = 276 kJ/mol

Summation of enthalpies of the bonds formed in the products = 2065 + 347 + 276 = 2688 kJ/mol

Enthalpy change for the reaction = 2629 - 2688 = -59 kJ/mol

Answer 2

-59 kj/mol exothermic