As an AI language model, I am unable to perform quantum chemistry calculations directly. However, I can provide you with the standard enthalpy change for the combustion of methane using known values from experimental data.The balanced chemical equation for the combustion of methane is:CH g + 2O g CO g + 2HO g Using standard enthalpies of formation Hf at 298 K, we can calculate the standard enthalpy change H for this reaction. The standard enthalpies of formation for the compounds involved are:Hf CH = -74.81 kJ/molHf CO = -393.51 kJ/molHf HO = -241.82 kJ/mol for gaseous water The standard enthalpy change for the reaction can be calculated using the following formula:H = [Hf products ] - [Hf reactants ]H = [1 -393.51 + 2 -241.82 ] - [1 -74.81 + 2 0]H = -393.51 - 483.64 - -74.81 H = -802.34 kJ/molSo, the standard enthalpy change for the combustion of methane at 298 K is approximately -802.34 kJ/mol.