Define the following terms :

(i) Abnormal molar mass

(ii) van’t Hoff factor – (i)

(i) Abnormal molar mass

The calculated molar mass of a substance which is either less or more than the one observed using the colligative properties of solutions is called abnormal molar mass. Abnormal molar mass generally occurs as a result of dissociation or association of molecules.

(ii) van’t Hoff factor – (i)

The ratio of observed colligative property to the calculated colligative property is known as van’t Hoff factor (i). Since colligative property is directly linked with molar mass, i is also defined as ratio of normal molar mass to abnormal molar mass.

i = =

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