The discussion revolves around methods for measuring the density of materials, specifically focusing on solid powders. Participants explore various techniques, including volume displacement and gas pycnometry, while addressing the challenges associated with measuring the density of powders compared to solid samples.
Participants express various viewpoints on the appropriate methods for measuring density, with no consensus reached on a single best approach. There are competing views on the effectiveness of different techniques, particularly regarding the use of water displacement versus gas pycnometry.
Participants highlight limitations in traditional methods for measuring density, particularly for powders, and the need for careful selection of measurement techniques based on material properties.
To determine the true density of solid powder particles, one therefore generally uses a helium gas pycnometer.epenguin said:Your liquid needs to be one that has no interaction with the solid, i.e. does not adsorb it nor dissolve in it. You don't want the solid floating on the liquid either.
Helium? Not heavy inert gases; small/fixed volumes times low densities equal small masses?Lord Jestocost said:uses a helium gas pycnometer.
Easier if you can just accept Bulk Density. Weigh the volume measurement container with and without your material. Note the volume measurement. Density, or in such a case, bulk density, is mass (which in your case might need to be "weight") divided by volume.EL AALLAOUI Najla said:yes I have a powder . thank you
"The problem with volume measurement is that object or substance isn't usually in a form of a regular shape but as a deformerd object or as a powder. Using classical method such as water diplacement isn't usually good enough since water could interact and become stuck on the sample surface. Gas pycnometry solves this by utilizing an inert gas and Boyle's gas law."Bystander said:Helium? Not heavy inert gases; small/fixed volumes times low densities equal small masses?