Use the bond energies H-H , Cl-Cl and H-Cl (all in kJ/mol) to find for .

Answer and explanation

Correct answer: B.

  1. Step 1: Bonds broken: kJ/mol (energy in).
  2. Step 2: Bonds formed: kJ/mol (energy out).
  3. Step 3: .
Answer
.
Why not the others: : subtracts in the wrong order: bonds formed minus bonds broken. : counts only the bonds formed. : adds all five bond energies together.

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