Final answer:
Option A: To break the bonds in NaCl, energy must be absorbed from the surroundings since bond breaking is an endothermic process.
Step-by-step explanation:
To break the bonds in NaCl, the reactant must absorb energy. The balanced chemical equation 2NaCl → 2Na + Cl₂ indicates that energy is required to break the ionic bonds in sodium chloride and separate it into sodium atoms and chlorine molecules. The breaking of bonds is an endothermic process, meaning it absorbs energy from the surroundings.
It takes energy to pull apart bonded atoms, as bonds are formed by the interactions of outer electrons within atoms. When bonds are broken, energy is put into the reaction. This is contrary to the formation of bonds, where energy is typically released. Therefore, in the case of splitting NaCl into its constituent elements, energy is absorbed from the surroundings to break the ionic bonds.
The reactant must (A) absorb energy
In the reaction 2NaCl → 2Na + Cl₂, the bonds in NaCl are being broken. Breaking bonds requires energy. In this case, breaking the bonds in NaCl requires the absorption of energy.