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

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

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.

  = –142 kJ

Bond:                             O–H          O=O           H–B    

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

Explanation:

The given reaction is as follows.

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

    = -142 kJ

Also, we know that

                  =

         -142 =

    = -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.

answer:

technetium is the most reactive. this is followed by silver. the least reactive out of these three elements is strontium.