Darwinism designates a distinctive form of evolutionary explanation for the history and diversity of life on earth. Its original formulation is provided in the first edition of On the Origin of Species in 1859.
The enthalpy - or internal energy - of a substance is a function of its temperature and pressure. The change in internal energy with respect to change in temperature at fixed pressure is the Specific Heat at constant pressure - cp.
Therefore, the energy of solution formation, the enthalpy of solution, equals the sum of the three steps: DHsoln = DH1 + DH2 + DH3. 1  The breaking of bonds requires or absorbs energy. This process is endothermic. 2  The formation of bonds releases energy. This process is exothermic.