Question

using the appropriate bond energies, calculate the heat of reaction δh for the following reaction: h−h + cl−cl → 2 h−cl 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. note: for clarity, all lone pairs have been omitted from the molecular structures. \\(\frac{\text{kj}}{\text{mol}}\\)

Explanation:

Step1: Recall bond energy formula

The formula for the heat of reaction (\(\Delta H\)) using bond energies is: \(\Delta H=\sum(\text{bond energies of reactants broken})-\sum(\text{bond energies of products formed})\).

Step2: Identify bonds broken/formed

• Reactants: 1 \(H - H\) bond and 1 \(Cl - Cl\) bond.
• Products: 2 \(H - Cl\) bonds.

Step3: Get bond energy values (standard values)

• Bond energy of \(H - H\): \(436\space kJ/mol\)
• Bond energy of \(Cl - Cl\): \(243\space kJ/mol\)
• Bond energy of \(H - Cl\): \(431\space kJ/mol\)

Step4: Calculate energy for reactants

Energy to break reactant bonds: \(E_{reactants}=E_{H - H}+E_{Cl - Cl}=436 + 243=679\space kJ/mol\)

Step5: Calculate energy for products

Energy released to form product bonds: \(E_{products}=2\times E_{H - Cl}=2\times431 = 862\space kJ/mol\)

Step6: Calculate \(\Delta H\)

\(\Delta H=E_{reactants}-E_{products}=679 - 862=- 183\space kJ/mol\)

Answer:

\(-183\)