1. **State the problem:** Determine whether the combustion of methane is exothermic or endothermic based on the given bond energies and reaction enthalpy. 2. **Recall definitions:** - An **exothermic** reaction releases heat, so $\Delta H_{\text{rxn}}$ is negative. - An **endothermic** reaction absorbs heat, so $\Delta H_{\text{rxn}}$ is positive. 3. **Given data for hexane combustion:** - Energy to break bonds (endothermic): $10,527$ kJ/mol - Energy released making bonds (exothermic): $-2,524$ kJ/mol - Net reaction enthalpy: $\Delta H_{\text{rxn}} = 8,003$ kJ/mol 4. **Interpretation:** - Since $\Delta H_{\text{rxn}} = 8,003$ kJ/mol is positive, the combustion of hexane as given is endothermic (absorbs heat). 5. **Combustion of methane:** - Typically, methane combustion is known to be exothermic. - The problem asks to circle one: exothermic or endothermic. 6. **Final answer:** - Combustion of methane is **exothermic**. **Summary:** - Hexane combustion as calculated here is endothermic. - Methane combustion is exothermic.