= Solution
The <functional group interaction profile> compares donor strength $\alpha$ and acceptor strength $\beta$. In <water>, strong–strong contacts compensate for <desolvation>, giving the upper-right black region. Strong–weak contacts lose favourable <solvent> interactions without adequate replacement, giving the two grey regions. Weak–weak association gives the lower-left black region through the <hydrophobic effect>.
Ethanol's ethyl groups preferentially solvate weakly polar sites, removing this incentive for their association: the lower-left region becomes approximately neutral. Its hydroxyl group retains competition for <hydrogen bonds> elsewhere in the profile.<Functional group interaction profiles: a general treatment of solvent effects on non-covalent interactions by Mark D. Driver and others>[Figures 4–5 and “Mixed polarity solvents”: water's hydrophobic quadrant and its elimination in ethanol]{ref}
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