Question

Use the table to answer the question:
Reaction
CH
+ 4Cl
à
CCl
+ 4HCl
Reactants
Products
Bonds Present
4 H-C
4 Cl-Cl
4 C-Cl
4 H-Cl
Energy of Bonds Broken (Reactants) / Formed(Products)
4 x 411kJ/mol
4 x 242kJ/mol
4 x 327 kJ/mol
4 x 427 kJ/mol
Which statement about the change in bond energy of this reaction is correct?
(1 point)
4
2
4
The reaction is endothermic because the energy of each bond in the reactants is less than the energy of a bondin the products.
The reaction is endothermic because the total bond energy of the reactants is greater than the total bondenergy of the products.
The reaction is exothermic because the total bond energy of the reactants is less than the total bond energy ofthe products.
The reaction is exothermic because the energy of each bond in the reactants is greater than the energy of abond in the products.

Answer 1

Option 3.

Calculation: bonds broken = 4(411) + 4(242) = 2612 kJ. Bonds formed = 4(327) + 4(427) = 3016 kJ. More energy is released forming bonds than is absorbed breaking them (net −404 kJ), so the reaction is exothermic because the total bond energy of the reactants is less than that of the products.