Question

Calculate the heat of reaction ΔH for the following reaction: CH4(g)+ 2O2(g)→CO2(g)+ 2H2O(g) You can find a table of bond energies by using the Data button on the ALEKS toolbar. Round your answer to the nearest /kJmol.

Answer 1

The heat of reaction (ΔH) for the given reaction can be calculated using bond energies. By subtracting the energy required to break the bonds in the reactants from the energy released when the bonds in the products are formed, we can determine the heat of reaction. In this case, the heat of reaction for CH4(g) + 2O2(g) → CO2(g) + 2H2O(g) is approximately -9972 kJ/mol.

Step-by-step explanation:

The heat of reaction (ΔH) for the given reaction can be calculated using bond energies. The bonds broken in the reactants and the bonds formed in the products contribute to the overall change in enthalpy.

For the reaction CH4(g) + 2O2(g) → CO2(g) + 2H2O(g), we can calculate the heat of reaction by subtracting the energy required to break the bonds in the reactants from the energy released when the bonds in the products are formed.

Using the given bond energies, we have:

• Bond energies for CH4: 4 x C-H = 1664 kJ/mol
• Bond energies for O2: 1 x O=O = 498 kJ/mol
• Bond energies for CO2: 2 x C=O = 2 x 730 kJ/mol
• Bond energies for H2O: 4 x O-H = 4 x 464 kJ/mol

Calculating the bond energy changes:

• Bonds broken: 4 x C-H = 4 x 1664 kJ/mol = -6656 kJ/mol
• Bonds formed: 2 x C=O = 2 x 730 kJ/mol = -1460 kJ/mol and 4 x O-H = 4 x 464 kJ/mol = -1856 kJ/mol

Summing up the bond energy changes:

• Total energy absorbed: -6656 kJ/mol
• Total energy released: -1460 kJ/mol from CO2 and -1856 kJ/mol from H2O

Using the signs of the energy changes, we can determine the heat of reaction ΔH = (-6656 kJ/mol) + (-1460 kJ/mol) + (-1856 kJ/mol) = -9972 kJ/mol. Rounded to the nearest /kJmol, the heat of reaction is approximately -9972 kJ/mol.

Answer 2

To calculate the heat of reaction (ΔH) for the given chemical reaction, you need to determine the bond energies of the reactants and products. By subtracting the total bond energy of the products from the total bond energy of the reactants, you can calculate ΔH.

Step-by-step explanation:

The question is asking to calculate the heat of reaction ΔH for the given chemical reaction: CH4(g) + 2O2(g) → CO2(g) + 2H2O(g).

Using the given table of bond energies, we can find the energy required to break the bonds in the reactants and the energy released when new bonds are formed in the products. Then, we can subtract the energy required to break the bonds from the energy released when new bonds are formed to calculate ΔH.

Let's calculate the bond energies and solve the problem:

Bond energy of C-H bond: 412 kJ/mol

Bond energy of O=O bond: 496 kJ/mol

Bond energy of O-H bond: 463 kJ/mol

Now, we can calculate the total bond energy for the reactants and the products:

Total bond energy of reactants: (4 x C-H bond energy) + (2 x O=O bond energy) = (4 x 412 kJ/mol) + (2 x 496 kJ/mol)

Total bond energy of products: (2 x C=O bond energy) + (4 x O-H bond energy) = (2 x 802 kJ/mol) + (4 x 463 kJ/mol)

Finally, we can calculate ΔH:

ΔH = Total bond energy of reactants - Total bond energy of products