How to Measure Viscosity of Liquids (page 2)

based on 35 ratings
Author: Beth Touchette


The actual times for the liquids will depend on the size of your viscometer and the temperature of your liquids. Your viscosity index for maple syrup should be 150-200 times that of water.  Most shampoos have 10-100 times the viscosity of water.


Viscosity is caused by friction within the liquid. Friction is the resistance one object encounters when moving over another. You probably remember that all matter, including liquids, is made of molecules. Water is composed of small simple molecules (H20).  These molecules can move past each other easily and quickly. Maple syrup, on the other hand, has a complex molecular structure—it’s composed of many different types of molecules, many of which are quite large. These big molecules do not move easily past one another, and they are often tangled together, giving syrup a much higher viscosity.

The viscosity of a liquid depends on the temperature. Increasing temperature usually decreases viscosity because the molecules have more energy to move past each other, and there is less intertwining. Water is used as the basis for the viscosity index because we are all familiar with how fast it moves.

You can test all kinds of liquids—but for some of them, like ketchup, be prepared to wait a very long time!

Add your own comment