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Question
Which of the following 0.10 m aqueous solutions will have the lowest freezing point?
Options
Al2(SO4)3
C5H10O5
KI
C12H22O11
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Solution
Al2(SO4)3
Explanation:
Freezing point depression depends on the number of particles in the Van’t Hoff factor (i). Al2(SO4)3 dissociates into 5 ions \[\ce{(2 Al^{3+} + 3 SO^2-_4)}\], producing the maximum number of particles, and hence causes the greatest depression in freezing point.
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