I learned about the resonance stability of ADP and the fact, that ATP is less stable due to intramolecular instability. I was surprised to see that the energy net of conversion of ADP to AMP is the same as ATP to ADP. Shouldn't the energy net of a reaction ADP to AMP+P be lower, because it's not so readily hydrolysed?
ATP has two high energy bonds which are phosphoanhydride bonds. Both bonds release the same amount of energy. Therefore, when ATP converts to ADP, breaks one phosphoanhydride bond, and releases -30.5 kJ/mol. When the 2nd bond is broken in ADP releases -30.5 kJ/mol because it is the same phosphoanhydride bond. However, AMP has only a phosphate ester bond which releases -61 kJ/mol.
The "less stability" of ATP doesn't affect energy yield.