Heat of Solution
A)is Never Positive $\Delta$ H°_soln $\le$ 0), Because the Solute-Solvent Attraction Is Never Weaker Than the 0)

Heat of solution

A) is never positive ( $\Delta$ H°_soln $\le$ 0) , because the solute-solvent attraction is never weaker than the combination of the solute-solute attraction and solvent-solvent attraction.
B) is always positive ( $\Delta$ H°_soln > 0) , because the solute-solvent attraction is always weaker than the combination of the solute-solute attraction and solvent-solvent attraction.
C) is always zero ( $\Delta$ H°_soln = 0) , because the solute-solvent attraction is defined as the average of the solute-solute attraction and solvent-solvent attraction.
D) is always negative ( $\Delta$ H°_soln < 0) , because the solute-solvent attraction is always stronger than the combination of the solute-solute attraction and solvent-solvent attraction.
E) may be positive, zero, or negative, depending on the relative strength of the solute-solvent, solute-solute, and solvent-solvent attractive forces.