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What is the bond dissociation energy of the carbon-hydrogen (C-H) bond in methane (CH4)? Show all steps of the calculation and include units.

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The bond dissociation energy  BDE  is the energy required to break a chemical bond. In this case, we are looking for the BDE of the carbon-hydrogen  C-H  bond in methane  CH4 . To find this value, we can refer to experimental data or use average bond energies.According to experimental data, the BDE of the C-H bond in methane is approximately 104 kcal/mol  435 kJ/mol . However, if we want to calculate the BDE using average bond energies, we can follow these steps:1. Determine the total energy of the bonds in the reactants.2. Determine the total energy of the bonds in the products.3. Calculate the difference between the total energies of the reactants and products.In this case, the reaction we are considering is the breaking of one C-H bond in methane:CH4  CH3 + HNow, let's find the average bond energies for the relevant bonds:C-H bond energy: 413 kJ/mol  from a table of average bond energies H-H bond energy: 436 kJ/mol  from a table of average bond energies Step 1: Determine the total energy of the bonds in the reactants.For methane  CH4 , there are 4 C-H bonds. Therefore, the total energy of the reactants is:4  C-H bonds   413 kJ/mol  C-H bond energy  = 1652 kJ/molStep 2: Determine the total energy of the bonds in the products.For the products, we have a methyl radical  CH3  and a hydrogen atom  H . Since we are only breaking one C-H bond, the total energy of the products is:3  C-H bonds   413 kJ/mol  C-H bond energy  = 1239 kJ/molStep 3: Calculate the difference between the total energies of the reactants and products.The bond dissociation energy of the C-H bond in methane is the difference between the total energies of the reactants and products:BDE = Total energy of reactants - Total energy of productsBDE = 1652 kJ/mol - 1239 kJ/mol = 413 kJ/molSo, the bond dissociation energy of the carbon-hydrogen  C-H  bond in methane  CH4  is approximately 413 kJ/mol. Note that this value is slightly different from the experimental value  435 kJ/mol  due to the use of average bond energies, which are not specific to methane.
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