Question

Determine the bond dissociation energy of methane (CH4) using the following data: Reaction: CH4(g) → C(g) + 4H(g)ΔH°f (kJ/mol): CH4(g) = -74.81C(g) = 715.32H(g) = 218.00Hint: bond dissociation energy can be calculated using the formula ΔH°rxn = Σ (ΔH°f, products) - Σ (ΔH°f, reactants)

Answer 1

To calculate the bond dissociation energy of methane  CH4 , we will use the given formula:Hrxn =   Hf, products  -   Hf, reactants First, let's find the total enthalpy of formation for the products:  Hf, products  = Hf  C g   + 4 * Hf  H g    Hf, products  = 715.32 kJ/mol + 4 * 218.00 kJ/mol  Hf, products  = 715.32 kJ/mol + 872.00 kJ/mol  Hf, products  = 1587.32 kJ/molNow, let's find the total enthalpy of formation for the reactants:  Hf, reactants  = Hf  CH4 g    Hf, reactants  = -74.81 kJ/molNow, we can calculate the bond dissociation energy using the formula:Hrxn =   Hf, products  -   Hf, reactants Hrxn = 1587.32 kJ/mol -  -74.81 kJ/mol Hrxn = 1587.32 kJ/mol + 74.81 kJ/molHrxn = 1662.13 kJ/molThe bond dissociation energy of methane  CH4  is 1662.13 kJ/mol.