Question

Calculate the heat of reaction AH for the following reaction: H (9) + Cl (9) + 2HCl(9) You can find a table of bond energies by using the Data button on the ALEKS toolbar. Round your answer to the nearest kJ/mol. 0 5 ? mol

Answer 1

The enthalpy change for the reaction of H₂ (g) + Cl₂ (g) → 2HCl (g) is -620 kJ/mol.

Step-by-step explanation:

To calculate the enthalpy change, AH, for the given reaction H₂ (g) + Cl₂ (g) → 2HCl (g), we need to consider the bond energies involved.

We can break down the reaction into bond breaking and bond forming steps. One mole of H-H bonds (bond energy = 436 kJ/mol) and one mole of Cl-Cl bonds (bond energy = 243 kJ/mol) need to be broken. On the other hand, two moles of H-Cl bonds (bond energy = 432 kJ/mol) will be formed.

The sum of the energy required to break the bonds minus the energy released by forming the bonds will give us the enthalpy change for the reaction.

Calculating the energy involved: (1 x 436 kJ) + (1 x 243 kJ) - (2 x 432 kJ) = -620 kJ/mol. Therefore, the enthalpy change for the reaction is -620 kJ/mol. Since the question asks for the answer to be rounded to the nearest kJ/mol, the final answer is -620 kJ/mol.

Answer 2

The enthalpy change (ΔH) for the given reaction can be calculated by subtracting the energy required to break the bonds from the energy released by forming the bonds. In this case, the enthalpy change is approximately -67 kJ/mol.

Step-by-step explanation:

The enthalpy change (ΔH) for the given reaction can be calculated using bond energies. In this case, one mole of H-H bonds (436 kJ/mol) and one mole of Cl-Cl bonds (243 kJ/mol) are broken, while two moles of H-Cl bonds (432 kJ/mol) are formed. The energy required to break the bonds is subtracted from the energy released by forming the bonds. Therefore, the total enthalpy change (AH) for this reaction is:

ΔH = (2 x 432 kJ/mol) - (1 x 436 kJ/mol + 1 x 243 kJ/mol)

Calculating this, we find that ΔH is approximately -67 kJ/mol.