Density Vs. Viscosity

Close-up of a student in a chemistry lab pouring water into a test tube
••• MicroBeans Studio/iStock/Getty Images

The expression 'slower than molasses in January' refers to two intrinsic properties of fluids: viscosity and density. Viscosity describes a liquid's resistance to flow—compare molasses and water, for example—and is measured in pascal-seconds. Density is a measure of the mass of a substance per unit volume and is measured in grams per milliliter.

How Slow Can You Flow?

Imagine a garden hose with no nozzle. If you turn on the tap, water will come shooting out the open end. However, if the pipes were filled with mud instead of water, you'd be lucky to get sporadic gobs coming out; mud has a higher viscosity than water. Generally, low-viscosity fluids, such as water, also have a low density. At a balmy 70 degrees Fahrenheit, water has a density of 0.99 grams per milliliter and a viscosity of 0.0009 pascal-seconds. Some metals are an exception to this trend. Liquid mercury has a density of 13.5 grams per milliliter and a viscosity of 0.016 pascal-seconds.

Related Articles

How to Convert CV to GPM
How to Calculate GPM from PSI for Water
How to Calculate CFM to MPH
Test Your Knowledge on Middle School Science
Brine Vs. Conductivity
How to Calculate Statistical Mean
How to Increase Amperes
How Are River Rocks Formed?
Characteristics of Aquatic Plants
Density Vs. Concentration
How to Convert Metric Tons to Cubic Meters
How to Convert KPa to Liters Per Minute
What Color Would a Tester PH Paper Turn if Is Dipped...
How Does Water Affect Sound?
How to Float an Egg in Water
How to Calculate Water Flow Through a Pipe Based on...
How to Convert mm Hg to in Hg
How to Find the Area of a Parallelogram
How to Convert Metric Tons to Barrels

Dont Go!

We Have More Great Sciencing Articles!