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Calculate the bond dissociation energy for the single bond in methane (CH4) given the following data: ΔHºf(CH4) = -74.8 kJ/molΔHºrxn = -890.4 kJ/mol Note: The bond dissociation energy is the amount of energy needed to break a bond between two atoms in a molecule, while keeping the other bonds intact.

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To calculate the bond dissociation energy for the single bond in methane  CH4 , we need to consider the reaction where one C-H bond is broken:CH4  CH3 + HFirst, we need to find the enthalpy change  H  for this reaction. We can use the given data to do this:Hf CH4  = -74.8 kJ/mol  enthalpy of formation of methane Hrxn = -890.4 kJ/mol  enthalpy change for the complete combustion of methane The complete combustion of methane can be represented by the following reaction:CH4 + 2O2  CO2 + 2H2ONow, we can use Hess's Law to find the enthalpy change for the bond dissociation reaction. Hess's Law states that the enthalpy change for a reaction is the same, regardless of the pathway taken. We can use the following steps:1. Reverse the formation reaction of methane:-CH4  -C + 4H  H = +74.8 kJ/mol 2. Add the complete combustion reaction:CH4 + 2O2  CO2 + 2H2O  H = -890.4 kJ/mol 3. Add the formation reactions of CO2 and 2H2O:C + 2O2  CO2  H = -393.5 kJ/mol 2H + O2  2H2O  H = -571.6 kJ/mol Now, we can sum up the reactions and their enthalpy changes:-CH4  -C + 4H  H = +74.8 kJ/mol CH4 + 2O2  CO2 + 2H2O  H = -890.4 kJ/mol C + 2O2  CO2  H = -393.5 kJ/mol 2H + O2  2H2O  H = -571.6 kJ/mol ---------------------------------------------3H  3H2O  H = ? Now, we can solve for the enthalpy change of the bond dissociation reaction:H = 74.8 - 890.4 + 393.5 + 571.6H = -74.8 + 74.8H = 0 kJ/molSince there are 4 C-H bonds in methane, we can divide the enthalpy change by 4 to find the bond dissociation energy for a single C-H bond:Bond dissociation energy = H / 4Bond dissociation energy = 0 kJ/molThe bond dissociation energy for the single bond in methane  CH4  is 0 kJ/mol.

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