1. The reason there is energy released in the process is because the products formed (ADP and hydrogenphosphate/phosphate) have stronger covalent bonds (plus intermolecular forces with the surrounding solution and dissolved ions) than the starting materials.
2. The end product of oxidative phosphorylation is ATP and water. ATP synthesis is coupled with the transfer of electrons to O2, which combines with protons to form water. Phosphorylation is the chemical addition of a phosphoryl group (PO3-) to an organic molecule. The removal of a phosphoryl group is called dephosphorylation. Both phosphorylation and dephosphorylation are carried out by enzymes (there are enzymes involved). kinases and phosphatases, From the family of Enzymes.
