The bond energy in 0=0 is 498 KJ/mole, how do you work out if it is an single bond or double does it change???

Question

how do you work out the bonds of all different compounds,

Answer 1

The bond energy of 498 kJ/mole is the amount of energy required to break the O=O double bond. It takes more energy to break a double bond than a single bond, and even more to break a triple bond. So you would expect the O-O single bond in a peroxide compound to have a bond energy of much less than 498 kJ/mole.

Answer 2

For molecules with just two atoms, the bond energy can be measured experimentally, by finding out the amount of energy from light that will make the molecule break apart. These bond energies are pretty exact.

For molecules with more atoms, bond energies are derived from these together with a best fit to account for the energy changes in chemical reactions. These bond energies have quite a large margin of error.