2 Mg(s) + O2(g) → 2 MgO(s) ΔH = -1204 kJ
Determine which statement is true regarding the reaction above.
A) The reaction is endothermic; the products have a lower total bond energy than the reactants.
B) The reaction is endothermic; the products have a higher total bond energy than the reactants.
C) The reaction is exothermic; the products have a lower total bond energy than the reactants.
D) The reaction is exothermic; the products have a higher total bond energy than the reactants.
Answer is C because since you are forming bonds, energy is released (exothermic). Since it is exothermic, the products will have lower energy than the reactants.