How does exothermic work?
Chemistry
Level
2
Fill in the blanks:
If a chemical reaction is exothermic, then the energy that is _______ when the bonds in the reactants are broken is _______ than the energy that is _______ when the bonds in the products form.
absorbed; less; released
None of these choices
absorbed; greater; released
released; greater; absorbed
released; less; absorbed
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1 solution
The separation of atoms in a molecule requires an increase in potential energy, so we must input energy for the reaction to proceed. Conversely, the forming of bonds between atoms causes a decrease in potential energy, which causes a release of energy. In an exothermic reaction, the enthalpy is negative, meaning there is a net decrease in potential decrease of the system. Thus, the absorbed energy to break the reactant bonds must be less than the released energy to form the product bonds.