For which of the following pair, the heat of mixing, ΔH_mix, is ≈ zero? — Solutions and Colligative Properties Chemistry Question

💡 Solution & Explanation

An ideal solution is formed when the solute-solute and solvent-solvent intermolecular forces are nearly equal to the solute-solvent intermolecular forces. Methanol ($CH_3OH$) and ethanol ($C_2H_5OH$) have very similar structures, sizes, and polarities, allowing them to form a nearly ideal solution with ΔH_mix ≈ 0.