Which aqueous solution will have the lowest freezing point? A)0.60 molal sucrose B)0.50 molal KF C)0.60 molal glucose D)0.24 molal FeI₃

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The solution with the lowest freezing point will have the highest van't Hoff factor, which depends on the nature of solute particles. KF dissociates into three ions (K+ and 2F-) when dissolved in water, giving it a van't Hoff factor of 3, whereas sucrose and glucose do not dissociate and have van't Hoff factors of 1. Fe(I₃) will not dissolve in water significantly, and so it is not an effective solute. Thus, the 0.50 molal KF solution will have the lowest freezing point due to its high van't Hoff factor.

Which Aqueous Solution Will Have the Lowest Freezing Point