What are the three chemical reasons for the large negative energy of hydrolysis of phosphoric acid anhydride linkage for compounds such at ATP, ADP, AND pyrophosphate?

The large negative energy of hydrolysis of phosphoric acid anhydride linkage in compounds such as ATP, ADP, and pyrophosphate can be attributed to three chemical reasons:

1. Electrostatic repulsion: Phosphorus in phosphoric acid anhydride linkage possesses a high positive charge, which is destabilized due to the presence of multiple oxygen atoms. The repulsion between like charges causes a buildup of potential energy within the molecule.

2. Resonance stabilization: In the anhydride linkage, the phosphorus atom donates electron pairs to the oxygen atoms, resulting in a partial positive charge on the oxygen atoms. This electron donation leads to resonance structures, where electron density shifts between different oxygen atoms. Resonance stabilization spreads the positive charge among the oxygen atoms, reducing the overall potential energy of the molecule.

3. Orthophosphate formation: Upon hydrolysis, the phosphoric acid anhydride linkage is broken and converted into orthophosphate ions. Orthophosphate ions are more stable due to the formation of stronger phosphorus-oxygen bonds. The release of energy during hydrolysis is a result of the formation of more stable products.

To summarize, the large negative energy of hydrolysis for compounds like ATP, ADP, and pyrophosphate is due to the combined effects of electrostatic repulsion, resonance stabilization, and the formation of more stable orthophosphate ions during hydrolysis.