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ChemistryMediumMCQ2019 · 12 Jan Shift 1

Q46.The freezing point of a 4% aqueous solution of X is equal to the freezing point of a 12% aqueous solution of Y . If the molecular weight of X is A , then the molecular weight of Y will be (1) 2A (2) A (3) 4A (4) 3A

What This Question Tests

This question requires applying the colligative property of freezing point depression to compare the molecular weights of two non-electrolyte solutions given their concentrations and equal freezing points.

Concepts Tested

Freezing point depressionMolalityVan't Hoff factor (for non-electrolytes)Molecular weight calculation

Formulas Used

ΔTf = Kf * m

m = (w₂/M₂) * (1000/w₁)

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