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Use the reaction to answer the question.CH4 + 202 CO₂ + 2H₂O-H-C: 412 kJ/molO=0: 496 kJ/molC-O: 743 kJ/molO-H: 463 kJ/molWhat is the total energy of the reaction?

Use the reaction to answer the question.CH4 + 202 CO₂ + 2H₂O-H-C: 412 kJ/molO=0: 496 kJ-example-1
User Wavyx
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1 Answer

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Answer:

The total energy reaction would be -698 kJ/mol.

Step-by-step explanation:

The formula to calculate the enthalpy change of a reaction is the following:


\Delta H=\Sigma Bond\text{ energy reactants-}\Sigma Bond\text{ energy products.}

Let's calculate the bond energy for each reactant:

- CH4: As we have 4 bonds of H - C, the bond energy is 4 x 412 kJ/mol = 1648 kJ/mol.

- O2: As we have 1 bond of O = O, but we have 2 moles of O2, we just multiply the bond energy of O = O by two: 2 x 496 kJ/mol = 992 kJ/mol.

Now, let's calculate the bond energy for each product:

- CO2: As we have 2 bonds of C - O (O - C - O), the bond energy would be 2 x 743 kJ/mol = 1486 kJ/mol.

- H2O: As we have 2 bonds of O - H (O - H - O), and 2 moles of H2O, we multiply the bond energy by the number of bonds, and the number of moles: 2 x 2 x 463 kJ/mol = 1852 kJ/mol.

Finally, we just apply the given formula, like this:


\begin{gathered} \Delta H=(1648+992)(kJ)/(mol)-(1486+1852)(kJ)/(mol), \\ \Delta H=(2640-3338)(kJ)/(mol), \\ \Delta H=-698(kJ)/(mol). \end{gathered}

The total energy reaction would be -698 kJ/mol.

User Knutsel
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