Unit of molal diffusivity is

A cm<sup>2</sup>/sec gm.mole
B gm moles/cm<sup>2</sup>.sec
C gm moles/cm.sec
D gm moles/cm<sup>3</sup>.sec

Correct Answer: cm<sup>2</sup>/sec gm.mole

Molal diffusivity (Dm) is a measure of how quickly a substance diffuses through a solvent when there is a concentration gradient between them.

The unit of molal diffusivity is typically expressed in terms of square centimeters per second (cm2/s) multiplied by the number of grams (gm) of the solute per mole (mole) of the solute.

So, the correct unit for molal diffusivity is cm2/sec gm.mole, which corresponds to option A.
Bissoy MCQ
#Chemical Engineering #Mass Transfer

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