Question

What is the bond dissociation energy for breaking all the bonds in a mole of o2 molecules?

Answer 1

Answer:

498 kj/mol

Explanation:

• Chemical reactions occur as a result of bond breaking and bond formation.
• The bonds in reactants are broken and atoms are rearranged to form new bonds.
• During bond breaking energy is absorbed to break the bonds of reactants while bond formation involves the release of energy during the formation of new bonds.

In our case;

In 1 mole of the Oxygen molecule, there is one O=O bond

Energy absorbed to break O=O is 498 kJ/mol

Therefore, the ΔH required to break all the bonds in one mole of Oxygen(O₂) molecules is 498kJ/mol.

Note that, bond breaking is endothermic since energy is absorbed  from the surroundings.