One mole of ADP undergoes a condensation reaction with inorganic phosphate to form 1 mole of ATP. This reaction requires the input of 32 kJ of energy, which is stored as chemical bond energy in the ATP until it is later released when 1 mole of ATP is hydrolyzed to form 1 mole of ADP and inorganic phosphate. The same quantity of energy is released in the hydrolysis reaction, a fact that illustrates the law of .

Conservation of energy

Explanation:

The law of conservation of energy or the first law of thermodynamics states that energy cannot be created or destroyed but can be transformed from one state to another. It can be transformed from Potential energy to Kinetic energy, to chemical energy, to mechanical energy and so on.

In the case above the condensation of ADP an inorganic phosphate stored up 32kJ of energy as ATP (potential energy). The hydrolysis of ATP to ADP and inorganic also releases 32kJ of energy (kinetic energy) the same value of energy that was initially stored up. This means that energy is been conserved.