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CHAPTER 2: Experimental Techniques 1: Direct Methods



Mark O. McLinden


Fluid density is mass per unit volume, and the experimental techniques described in this chapter involve, in one way or another, a clearly defined mass and volume. For this reason, we describe them as “direct” methods. This is in contrast to the vibrating-tube method described in Chapter 3, in which neither mass nor volume are measured directly, but, rather, the fluid density is calibrated in terms of the resonant frequency of the vibrating body. The direct methods described here range from very simple and inexpensive devices to highly sophisticated instruments that have determined the most accurate fluid densities measured to date. Densimeters combining the Archimedes principle with a magnetic suspension coupling are increasingly used for wide-ranging, high-accuracy measurements, and such devices are extensively discussed. Older techniques are also described.
Volume Properties: Liquids, Solutions, and Vapours
Publisher Info
Royal Society of Chemistry, RSC Publishing, Cambridge, -1


experiment, magnetic suspension densimeter, Archimedes densimeter, hydrometer, pycnometer, Burnett method, isochoric densimeter, voluometer


McLinden, M. (2014), CHAPTER 2: Experimental Techniques 1: Direct Methods, Royal Society of Chemistry, RSC Publishing, Cambridge, -1, [online], (Accessed July 18, 2024)


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Created December 17, 2014, Updated November 10, 2018