Answer to Question #26516 in Physical Chemistry for zameer

Question

Explain the following terms:
i) Integral enthalpy of solution
ii) Differential enthalpy of solution
iii) Enthalpy of dilution

Answer 1

I. Integral Enthalpy Of Solution is the heat absorbed or released when a solute is dissolved in a definite amount of solvent. The heat of solution depends on the nature of the solute and on its concentration in the final solution. The integral heat of solution when one mole of solute is added to an infinite amount of solvent is sometimes written as deltahinfty, soln.
II. Differential heat of solution is the partial derivative of the total heat of solution with respect to the molal concentration of one component of the solution, when the concentration of the other component or components, the pressure, and the temperature are held constant.
III. Enthalpy of dilution is the enthalpy change associated with the dissolution of a substance in a solvent at constant pressure resulting in infinite dilution. Enthalpy of dilution is most often expressed in kJ/mol at constant temperature. The energy change can be regarded as being made of three parts, the endothermic breaking of bonds within the solute and within the solvent, and the formation of attractions between the solute and the solvent. An ideal solution has an enthalpy of solution of zero.