In the following reaction, the energy of the reactants is 1240 kJ/mol, and the bond energy of the products is 1790 kJ/mol. What is the total energy of the reaction? Is the reaction endothermic or exothermic?

Question

A. 3030 kJ/mol, endothermic
B. -3030 kJ/mol, exothermic
C. 550 kJ/mol, endothermic
D. -550 kJ/mol, exothermic

Answer 1

The total energy of the reaction can be found by taking the difference between the energy of the reactants and the bond energy of the products:

Total energy = bond energy of products - energy of reactants
Total energy = 1790 kJ/mol - 1240 kJ/mol
Total energy = 550 kJ/mol

Since the total energy is positive, the reaction is endothermic. Therefore, the correct answer is C. 550 kJ/mol, endothermic.