Ultra-centrifugation used to purify colloidal solution is based on the difference of

Options

A. electrical change
B. density
C. size
D. all of these

Answer

B

Explanation

In this method, the colloidal sol is taken in a tube which is placed in an ultra-centrifuge. On rotation of the tube at high speeds, the colloidal particles being more dense settle down at the bottom of the tube and the impurities remain in the solution called centrifuge. The settled colloidal particles are mixed with an appropriate dispersing medium to regenerate the sol.