Class 12th Chemistry 2017 Set3 Delhi Board Paper Solution
Define the following terms:
a) Abnormal molar mass
b) Van’t Hoff factor
a) Abnormal molar mass : When the molecular mass of a substance as determined by studying any of the colligative properties is different than the theoretically expected value, then the substance will have abnormal molecular mass.
b) Van’t Hoff factor: an't Hoff's factor (i) is defined as the ratio of the observed colligative property to the calculated colligative property.
i = Observed colligative property / Calculated colligative property
Observed colligative property ∝ 1/Molar Mass
i = Mc/Mo
Van't Hoff's factor (i) represents the extent of association (or) dissociation of a solute.
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