Experiment 11


Determine the relative viscosity of the liquid with respect to water at room temperature by Ostwald's viscometer.


Distilled water, stop watch, viscometer (Ostwald's), unknown liquid, pyknometer or R.D. bottle, pipette etc.


Ostwald's viscometer is a U-shaped glass tube as shown in the Fig. Ex 11.1. In one arm, the bulb A is connected with a fine capillary. The lower end of the capillary is connected with a U tube provided with a bulb B in the second arm. The bulbs are necessary to maintain the hydrostatic pressure during the flow of liquid. Through the capillary tube, the liquid flows with measurable speed. There are two marks C and D above and below the bulb A. The upper end of the bulb A is attached ...

Get Pharmaceutical Physical Chemistry: Theory and Practices now with O’Reilly online learning.

O’Reilly members experience live online training, plus books, videos, and digital content from 200+ publishers.