Problem: Enthalpy changes accompanying the solution process.How does the magnitude of Hmix compare with the magnitude of Hsolvent+Hsolute for exothermic solution processes?

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Two diagrams have enthalpy, H (increasing, unscaled) on the y-axis and show delta H for the solute, solvent, mix and solution for both an exothermic and endothermic solution process. Exothermic solution process: A horizontal line about 1/3 of the way up the y-axis is Hinitial. Delta Hsolvent is the increase in enthalpy from delta Hinitial to halfway up the y-axis as solvent intermolecular attractions are broken. Similarly, delta Hsolute is the increase in enthalpy from Hinitial to a point a bit higher than delta Hsolvent as solute intermolecular attractions are broken. Delta Hsolvent plus delta Hsolute is an increase in enthalpy from Hinitial to near the top of the y-axis. Delta Hsolution is less than 0, and is the decrease in enthalpy from Hinitial to near the bottom of the y-axis at Hfinal. Delta Hmix is the change in enthalpy from delta Hsolvent plus delta Hsolute to Hfinal. For an endothermic solution process, the magnitudes of the enthalpy changes are different, and delta Hsolution is greater than 0 rather than less than 0. Hinitial is lower in the endothermic than exothermic process, and is about ¼ of the way up the y-axis rather than 1/3, but the magnitude of delta Hsolvent, is greater. By contrast, the magnitude of delta Hsolute is less, and is lower than delta Hsolvent. Delta Hsolvent plus delta Hsolute rises to the same point on the y-axis as in the exothermic solution process, so the magnitude of this factor is greater, as Hinitial is lower. Delta Hsolution is greater than 0, and is the distance from Hinitial to Hfinal, which is a point on the y-axis just below delta Hsolute. Delta Hmix is thus a much lower magnitude than it is in the exothermic solution process, as it is the distance from Hsolvent plus delta Hsolute to Hfinal.
Enthalpy changes accompanying the solution process.

How does the magnitude of Hmix compare with the magnitude of Hsolvent+Hsolute for exothermic solution processes?

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