AB2 is a molecule that reacts readily with water. Calculate the bond energy of the A–B bond using the standard enthalpy of reaction and the bond energy data provided. Enter a number in kJ to 0 decimal places. 2AB2(g) + 2H2O(g) ⟶ O=O(g) + 4HB(g) + A2 ΔH° = –142 kJ

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Given question is incomplete. The complete question is as follows.

[tex]AB_{2}[/tex] is a molecule that reacts readily with water. Calculate the bond energy of the A–B bond using the standard enthalpy of reaction and the bond energy data provided. Enter a number in kJ to 0 decimal places.

  [tex]2AB_{2}(g) + 2H_{2}O(g) \rightarrow O=O(g) + 4HB(g) + A_{2}[/tex] [tex]\Delta H^{o}[/tex] = –142 kJ

Bond:                             O–H          O=O           H–B    [tex]A \rightarrow A^{+}[/tex]

Bond energy (kJ/mol):   467         498           450         321      

Explanation:

The given reaction is as follows.

         [tex]2AB_{2} + 2H_{2}O \rightarrow O_{2} + 4HB + A_{2}[/tex]

Now, we will calculate the enthalpy of reaction as follows.

   [tex]\Delta H^{o}_{R}[/tex] = -142 kJ

Also, we know that

   [tex]\Delta H^{o}_{R} = \Delta H_{reactants} - \Delta H_{products}[/tex]

                  = [tex][(2 \times 2 (A-B) + 2 \times 2 (O-H)] - [(O=O) + 4(H-B) + (A-A)][/tex]

         -142 = [tex]4(A-B) + 4 \times 467 - 498 - 4(450) - 321[/tex]

    [tex]4(A-B)[/tex] = -142 - 1868 + 498 + 1800 + 321

                    = 609

          (A-B) = 152.25 kJ/mol

Thus, we can conclude that the bond energy of the A–B bond is 152.25 kJ/mol.